Shielding unit and vacuum deposition device equipped with said shielding unit

Abstract

Provided is a shielding unit for a vacuum deposition device, the shielding unit being provided in a vacuum chamber 1 so that, during vacuum treatment conducted in the vacuum chamber having a vacuum atmosphere, a prescribed amount of light of a prescribed wavelength range from a component present in the vacuum chamber passes through an inspection window 7 provided in the chamber wall. The shielding unit inhibits contaminants resulting from the vacuum treatment from adhering to the inspection window, and reduces the frequency of inspection window replacements.　The shielding unit includes: a first shielding part 8a disposed in front of the inspection window and allowing transmission of the light of the prescribed wavelength range; and a second shielding part 8b disposed in front of the first shielding part. The second shielding part is composed of plate-like members each having, along the circumferential direction, a plurality of through holes 88a, 88b penetrating in the front-rear direction, and driving motors 83a, 83b for rotationally driving the second shielding part are provided.

Description

Shielding unit and vacuum deposition apparatus equipped with this shielding unit

[0001] The present invention relates to a shielding unit and a vacuum deposition apparatus equipped with the shielding unit.

[0002] For example, vacuum deposition apparatuses have been used to form metal films on the surfaces of substrates such as glass or silicon wafers, or sheet-like substrates such as resin substrates (hereinafter also referred to as "substrates") in a vacuum atmosphere. As a deposition source for this type of vacuum deposition apparatus, one using a deposition boat is known, for example, from Patent Document 1. The deposition boat includes a boat body having a deposition material storage compartment and electrode mounting plates extending outward from the upper end of the boat body. The two electrode mounting plates are held (sandwiched) by a pair of upper and lower electrode plates, respectively, and are installed in a vacuum chamber. During deposition on the substrate in a vacuum chamber under a vacuum atmosphere, the boat body is heated by Joule heat by applying current between the two electrode mounting plates via the electrode plates from a power source. Then, a wire-shaped deposition material made of a metal, such as copper or aluminum, is supplied from above the bottom plate of the boat body, which defines the storage compartment, so as to abut against the bottom plate. The deposition material then melts and spreads inside the container, evaporating from the surface of the molten metal that has spread, and the evaporated deposition material adheres to the object to be deposited, depositing a copper film or aluminum film onto the object.

[0003] During deposition on the substrate, the amount of molten metal in the container increases or decreases, causing bumping, which can result in the deposition material not evaporating but instead splashing from the molten metal surface and adhering to the substrate, resulting in poor product yield. For this reason, it is known to provide a camera (imaging device) that captures images of the deposition boat, a component present in the vacuum chamber, and analyze the captured images to control the current value and supply rate when applying electricity to the deposition boat (see, for example, Patent Document 2). In such cases, a viewing window is provided on the wall of the vacuum chamber, and light within a predetermined wavelength range from the deposition boat is received by the imaging device through the viewing window. However, during deposition on the substrate, the deposition material adheres to the inner surface of the viewing window as a contaminant, gradually reducing the amount of light passing through the viewing window.

[0004] If the amount of light passing through the sight glass falls below a predetermined range, it becomes impossible to capture images with the imaging device of the deposition boat, so deposition on the deposition target must be stopped and the sight glass must be replaced. If the sight glass is replaced more frequently, the deposition time on the deposition target becomes shorter, resulting in a decrease in productivity. Moreover, if a relatively expensive material such as sapphire glass is used as the sight glass to stabilize the optical characteristics, frequent replacement of the sight glass will result in a rise in running costs.

[0005] Japanese Patent Application Laid-Open No. 2007-46106 Japanese Patent Application Laid-Open No. 2020-507610

[0006] In view of the above, an object of the present invention is to provide a shielding unit that can reduce the frequency of replacing the observation window, and a vacuum deposition apparatus equipped with this shielding unit.

[0007] In order to solve the above problems, the present invention provides a shielding unit that is provided in a vacuum chamber so that a predetermined amount of light in a predetermined wavelength range from a component present in the vacuum chamber is transmitted through a sight glass provided in a wall of the vacuum chamber during vacuum processing in the vacuum chamber, thereby suppressing adhesion of contaminants generated by the vacuum processing to the sight glass. The shielding unit includes a first shielding portion disposed in front of the sight glass and allowing transmission of light in the predetermined wavelength range, and a second shielding portion disposed in front of the first shielding portion, the second shielding portion being formed of a plate-like member having a plurality of through holes extending therethrough in the front-rear direction along the circumferential direction, and a drive motor for rotating the second shielding portion. In this case, a configuration may be adopted in which the shielding unit further includes an openable / closable shutter disposed in front of the second shielding portion.

[0008] According to the present invention, taking a case where the vacuum process is a vacuum deposition process as an example, during deposition on a deposition target, deposition material (contaminants) from the deposition source are scattered toward the sight glass, but most of the deposition material adheres to the first shielding portion located in front of the sight glass, and adhesion of the deposition material to the sight glass is significantly suppressed, so that the sight glass does not need to be replaced frequently. Moreover, since the first shielding portion itself is made of a material that transmits light in a predetermined wavelength range and the second shielding portion has a plurality of through holes that allow light to pass through, light in the predetermined wavelength range intermittently passes through the sight glass, and therefore the function of the sight glass is not impaired even when the light passing through the sight glass is received and the deposition boat is imaged with an imaging device.

[0009] During deposition on the deposition target, the deposition material that passes through each through-hole in the second shielding part also adheres to the front surface of the first shielding part, eventually reducing the amount of light. However, because the second shielding part rotates, the amount of deposition material that adheres to the front surface of the first shielding part can be dispersed in its circumferential direction. Therefore, compared to when the deposition material directly adheres to the inner surface of the sight glass, the time until the light amount decreases beyond a predetermined range can be significantly extended. As a result, combined with the provision of a shutter that allows light to pass through the sight glass only when necessary for imaging with the imaging device, it is possible to minimize increases in running costs even when a relatively expensive material is used for the second shielding part.

[0010] In the present invention, the first shielding portion may be composed of a plate-like member arranged in a row with a gap between it and the second shielding portion in the front-rear direction, and the second shielding portion may be rotated asynchronously with the first shielding portion. This advantageously allows the amount of vapor deposition material adhering to the front surface of the first shielding portion to be further dispersed in the circumferential direction. On the other hand, the first shielding portion may be composed of a sheet-like member that crosses the rear side of the second shielding portion in one direction, and may be provided with a payout roller that pays out the sheet-like member and a take-up roller that winds up the sheet-like member. This advantageously allows the sheet-like member to be restored to its initial state simply by further paying out a predetermined length when the vapor deposition material adheres to the front surface of the sheet-like member and the light intensity decreases, thereby reducing the frequency of replacement of the second shielding portion, which requires opening the vacuum chamber to the atmosphere.

[0011] In order to solve the above-mentioned problems, the present invention provides a vacuum deposition apparatus that includes the shielding unit according to claim 1 or 2, and further includes a deposition boat that is disposed in the vacuum chamber and has a deposition material storage section therein, and a material supply unit that supplies wire-shaped deposition material from above so as to abut against a bottom plate of the deposition boat that defines the storage section, and that performs deposition on a deposition target in the vacuum chamber as the vacuum processing. The vacuum deposition apparatus is characterized in that the first shielding unit includes a first rotation shaft and a second rotation shaft that are disposed parallel to each other, and a first rotating plate and a second rotating plate that are extrapolated onto the first rotation shaft and the second rotation shaft, respectively, and the first rotating plate and the second rotating plate are made of different materials corresponding to the wavelength ranges of light received by the respective imaging devices.

[0012] 1 is a schematic cross-sectional view of a vacuum deposition apparatus including a shielding unit according to an embodiment of the present invention; 2 is a schematic cross-sectional view of the shielding unit as viewed from the deposition chamber side; 3 is a cross-sectional view taken along line III-III in FIG. 2; 4 is a cross-sectional view of a shielding unit according to a modified example corresponding to FIG. 3; 5 is a cross-sectional view of a shielding unit according to another modified example corresponding to FIG. 3;

[0013] Hereinafter, with reference to the drawings, an embodiment of the shielding unit SU and vacuum deposition apparatus ES of the present invention will be described using as an example a case in which the vacuum treatment is vacuum deposition, the deposition target is a sheet-like substrate Sw, a component present in a vacuum chamber is a deposition boat, and a wire-shaped aluminum deposition material Em is supplied to the deposition boat 3 and evaporated to deposit an aluminum film on one side of the sheet-like substrate Sw in a vacuum chamber under a vacuum atmosphere. In the following, terms indicating directions such as up and down are, in principle, based on Figure 1, which shows the installation position of the apparatus.

[0014] 1, the vacuum deposition apparatus ES is a so-called winding type, and includes a vacuum chamber 1. A vacuum pump unit Pu, which is composed of a turbomolecular pump, a rotary pump, or the like, is connected to the vacuum chamber 1 via an exhaust pipe Ep, and a vacuum atmosphere (e.g., 10 －５ Pa) can be formed. The interior of the vacuum chamber 1 is divided into two chambers, an upper chamber and an lower chamber, by a partition plate 11. In FIG. 1, a transport unit 2 that transports the sheet-like substrate Sw at a constant speed is disposed in the transport chamber Ts located on the upper side. The transport unit 2 includes a payout roller 21 around which the sheet-like substrate Sw is pre-wound and which is driven to rotate by a motor 21a to pay out the sheet-like substrate Sw at a constant traveling speed, and a take-up roller 22 that is driven to rotate by a motor 22a to take up the sheet-like substrate Sw after the film formation. Inside an opening 12 formed in the partition plate 11, a can roller Cr is disposed facing a deposition boat 3 described below, around which a portion of the sheet-like substrate Sw is wound. The transport chamber Ts also includes a plurality of guide rollers Gr appropriately provided to guide the sheet-like substrate Sw paid out from the payout roller 21 to the can roller Cr and to guide the film-formed sheet-like substrate Sw from the can roller Cr to the take-up roller 22. On the other hand, in the vapor deposition chamber Vs located at the lower side in FIG. 1, a vapor deposition boat 3 is disposed as a vapor deposition source for vapor deposition on the portion of the substrate Sw wound around the can roller Cr.

[0015] The evaporation boat 3 includes a boat body 31 having a flat bottom and a recess 31a serving as a storage area for the evaporation material Em, and electrode mounting plates 32 extending horizontally outward from both longitudinal ends (left-right direction in FIG. 1 ) of the boat body 31. The evaporation boat 3 is integrally formed by pressing a metal plate having a higher melting point than the evaporation material Em. Examples of high-melting-point metals include molybdenum, tungsten, and tantalum. The evaporation boat 3 may also be made of a ceramic material such as boron nitride, carbon, or oxides and nitrides of aluminum or titanium. Two support bases 4, 4 made of an insulating material are installed on the inner surface 1a of the lower wall of the vacuum chamber 1, spaced apart in the longitudinal direction. A pair of upper and lower electrode plates 5a, 5b made of a highly conductive metal such as copper are detachably attached to the upper surfaces of the support bases 4, 4 by fastening means 41 such as bolts, while sandwiching the electrode mounting plates 32, 32 of the evaporation boat 3 from above and below.

[0016] When the electrode plates 5a, 5b holding the electrode mounting plates 32, 32 are attached, the evaporation boat 3 is installed at a predetermined height from the inner surface 1a of the lower wall of the vacuum chamber, with the bottom plate of the boat body 31 defining the recess 31a in a horizontal position. A known constant-voltage control power supply Ps is connected to each of the electrode plates 5a, 5b. The boat body 31 can be heated by Joule heat by applying electricity between the electrode mounting plates 32, 32 from the constant-voltage control power supply Ps via the electrode plates 5a, 5b. An ammeter Am is provided in the electrical circuit between the constant-voltage control power supply Ps and the electrode mounting plates 32, 32 to measure the current value when electricity is applied at a constant voltage. The evaporation chamber Vs is equipped with a material supply unit 6 for continuously or intermittently supplying wire-shaped evaporation material Em to the recess 31a of the boat body 31.

[0017] The material supply unit 6 includes a feed roller 61 installed on the side of the deposition shield 13 arranged in the deposition chamber Vs facing away from the deposition boat 3, a motor 62 that rotates and drives the feed roller 61, and a pair of upper and lower guide rollers 63, 63. A through hole 13a is provided at a predetermined position in the deposition shield 13, through which a wire-shaped deposition material Em passes. A guide tube 64 of a predetermined length with its tip bent downward is attached to the surface of the deposition shield 13 facing the deposition boat 3, surrounding the through hole 13a, to guide the deposition material Em toward the recess 31a of the boat body 31. The deposition material Em is formed to an outer diameter of 1 mm to 5 mm and is wound around the feed roller 61 in advance. A viewing window 7 is provided in the side wall 1b of the vacuum chamber 1, and multiple imaging devices are provided to capture images while receiving light in a predetermined wavelength range from the deposition boat 3 through the viewing window 7.

[0018] In this embodiment, during deposition on the sheet-like substrate Sw, the first to third imaging devices Is are used to monitor (1) the supply position of the tip Em1 of the deposition material Em to the accommodation section 31a, (2) the surface temperature of the molten metal of the deposition material Em that has wetted and spread within the accommodation section 31a, and (3) the spreading state of the molten metal in the accommodation section 31a. １ ~Is ３ The first imaging device Is １ For example, a CCD camera that receives and captures light (visible light) in the wavelength range of 350 nm to 800 nm is used as the second imaging device Is ２ A radiation thermometer (two-color thermometer) that receives light in the wavelength range of 0.5 μm to 1.6 μm and converts the temperature from the ratio of radiance is used as the third imaging device Is ３ A thermal camera that captures images by receiving light in the wavelength range of 7 μm to 14 μm (far-infrared light) is used as the imaging device. １ ~Is ３ Since known ones are used as the filter, detailed explanations are omitted here.

[0019] Although not shown in detail, the viewing window 7 has a circular metal support plate, and the first to third image capturing devices Is are attached to the support plate. １ ~Is ３Three through holes (not shown) are provided corresponding to the light receiving sections of the first and second image capturing devices Is. １ , Is ２ The through holes corresponding to the third imaging device Is are provided with, for example, sapphire windows. ３ A germanium window, for example, is attached in an airtight and detachable manner to the through-hole corresponding to the peephole 7. A shielding unit SU of this embodiment is provided in the vacuum chamber 1 so that a predetermined amount of light in the above wavelength range passes through the peephole 7 during deposition on the sheet-like substrate Sw in the vacuum chamber 1 under a vacuum atmosphere. Specifically, a storage chamber Hs is provided in the vacuum chamber 1 corresponding to the peephole 7, and the shielding unit SU is disposed in the storage chamber Hs. Hereinafter, the side facing inward from the side wall 1b of the vacuum chamber 1 where the peephole 7 is located will be referred to as the front, and the side facing the side wall 1b from inside the vacuum chamber 1 will be referred to as the rear.

[0020] 2 and 3, the shielding unit SU has a first shielding portion 8a disposed in front of the viewing window 7 to allow transmission of light in the above wavelength range, and a second shielding portion 8b disposed in front of the first shielding portion 8a. The first shielding portion 8a has a first rotation shaft 81a and a second rotation shaft 81b disposed parallel to each other, and a first rotation plate 82a and a second rotation plate 82b respectively fitted onto the first rotation shaft 81a and the second rotation shaft 81b. The first rotation plate 82a is made of, for example, acrylic resin or polycarbonate, and is attached to the first and second imaging devices Is. １ , Is ２ The second rotary plate 82b, which is offset rearward from the first rotary plate 82a, is made of, for example, germanium, silicon, or AR-coated glass, and is configured as a plate-shaped member having an area large enough to cover the front surface of the light receiving portion of the third image pickup device Is. ３ In this embodiment, the first rotating plate 82 a and the second rotating plate 82 b each have a circular outline and are configured to cover the entire front surface of the observation window 7. This prevents the evaporation material Em scattered from the evaporation boat 3 from directly adhering to the observation window 7.

[0021] Drive motors 83a, 83b are provided on the upper wall Hs1 and the lower wall Hs2 that define the storage chamber Hs, and bevel gears 84a, 84b are provided on the tip of the output shaft of each drive motor 83a, 83b. Bevel gears 85a, 85b are provided on the rear ends of the first rotating shaft 81a and the second rotating shaft 81b, respectively, and the bevel gears 84a, 84b mesh with the bevel gears 84a, 84b, respectively, to rotate the first rotating plate 82a and the second rotating plate 82b at a predetermined rotation speed. Furthermore, reduction gears 86a and 86b are respectively provided on the first and second rotating shafts 81a and 81b, and a third rotating plate 87a and a fourth rotating shaft 87b as the second shielding portion 8b are respectively offset in the front-rear direction and extrapolated to the portions of the first and second rotating shafts 81a and 81b located forward of the reduction gears 86a and 86b. As a result, the third rotating plate 87a and the fourth rotating plate 87b are rotated asynchronously with the first rotating plate 82a and the second rotating plate 82b, respectively. The number of rotations in this case depends on the area of ​​the through-hole 88a and the number of rotations of each imaging device Is. １ , Is ２ The exposure time is appropriately set taking into consideration the exposure time.

[0022] The third rotary plate 87a, which is arranged next to the first rotary plate 82a, is made of, for example, stainless steel and has the same area as the first rotary plate 82a. The third rotary plate 87a also has a plurality of slit-shaped through-holes 88a that extend in the circumferential direction and penetrate in the thickness direction of the plate at predetermined intervals in the circumferential direction. In this case, the length and width of the through-holes 88a are set to be equal to the length and width of the first and second imaging devices Is. １ , Is ２ The fourth rotary plate 87b is also made of, for example, stainless steel and has the same area as the second rotary plate 82b. A plurality of slit-shaped through holes 88b extending circumferentially and penetrating the plate thickness direction are formed at predetermined intervals in the circumferential direction. The fourth rotary plate 87b is also made of, for example, stainless steel and has the same area as the second rotary plate 82b. The fourth rotary plate 87b has a plurality of slit-shaped through holes 88b extending circumferentially and penetrating the plate thickness direction at predetermined intervals in the circumferential direction. In this case, the length, width, and number of the through holes 88a are set in the same manner as above.

[0023] A through-hole 89 is formed in the front wall Hs3 that defines the storage chamber Hs, and a shutter 9 is provided to cover the through-hole 89 in an openable and closable manner. The shutter 9 is made of, for example, a stainless steel plate member, and is moved forward and backward by an air cylinder (not shown). The vacuum deposition apparatus ES is equipped with a control unit Uc. The control unit Uc is a well-known unit having a microcomputer, a sequencer, a memory, etc., and controls the vacuum pump Pu, motors 21a and 22a, motor 62 of the material supply unit 6, constant voltage control power supply Ps, shielding unit SU, and each of the first to third imaging devices Is. １ ~Is ３ The control unit Uc also controls the operation of the first to third image capture devices Is. １ ~Is ３ Image data captured by the image sensor 10 is input, and the input image data is analyzed, and the constant voltage control power supply Ps and the material supply unit 6 can be controlled based on the analyzed image data. A method for vacuum-depositing an aluminum film onto a sheet-like substrate Sw using the vacuum deposition apparatus ES will be described below.

[0024] When an aluminum film is vapor-deposited on a sheet-like substrate Sw in a vacuum chamber 1 under a vacuum atmosphere using the vacuum vapor deposition apparatus ES, the boat body 31 is heated by Joule heat by applying current between the electrode mounting plates 32, 32 via the electrode plates 5a, 5b using a constant-voltage control power supply Ps. After a predetermined time has elapsed, the motor 62 rotates the feed roller 61 to feed out a wire-like vapor deposition material Em at a predetermined speed. The tip Em1 of the vapor deposition material Em, which contacts the bottom plate of the boat body 31 defining the storage section 31a, gradually melts and spreads, and the vapor deposition material Em on the wetted and spread surface evaporates. Simultaneously, the motors 21a, 22a of the transport unit 2 are rotated to feed out the sheet-like substrate Sw at a constant traveling speed. As a result, the evaporated vapor deposition material Em adheres to the portion of the sheet-like substrate Sw wrapped around the can roller Cr, thereby vapor-depositing an aluminum film. The deposition rate at this time is set to, for example, a range of 200 mm / min to 2000 mm / min.

[0025] When monitoring the above (1) to (3) during deposition on the sheet-like substrate Sw, the shutter 9 is moved to the open position (the state shown in FIG. 2), and the first rotating shaft 81a, the second rotating shaft 81b, the third rotating plate 87a, and the fourth rotating plate 87b are rotated asynchronously by the respective drive motors 83a, 83b. １ ~Is ３ The evaporation boat 3 is imaged by the image sensor 10, and the image data of the image is input to the control unit Uc. Based on this, the control unit Uc controls, for example, the constant-voltage control power supply Ps and the material supply unit 6 so that the amount of evaporation material Em in the evaporation boat 3 is kept substantially constant.

[0026] According to the above, during imaging of the deposition boat 3, the deposition material Em from the deposition boat 3 also scatters toward the observation window 7 through the through hole 89. However, most of the deposition material Em adheres to the front surfaces of the first rotating shaft 81a, the second rotating shaft 81b, the third rotating plate 87a, and the fourth rotating plate 87b of the shielding unit SU, and adhesion of the deposition material Em to the observation window 7 is significantly suppressed. Therefore, the observation window 7 does not need to be replaced frequently. Moreover, the first rotating plate 82a and the second rotating plate 82b serving as the first shielding part 8a are made of a material that transmits light in the above wavelength range, and the third rotating plate 87a and the fourth rotating plate 87b serving as the second shielding part 8b have a plurality of through holes 88a, 88b that allow light to pass through. Therefore, light in the above wavelength range intermittently passes through the observation window 7, and the first to third imaging devices Is １ ~Is ３ Therefore, the imaging function of the deposition boat 3 is not impaired.

[0027] Furthermore, during deposition on the sheet-like substrate Sw, the deposition material Em passing through each through-hole 88a, 88b also adheres to the front surfaces of the first and second rotary plates 82a, 82b, eventually decreasing the light intensity. However, because the first and second rotary plates 82a, 82b are rotated at a predetermined rotation speed, the amount of deposition material Em adhering thereto can be dispersed in the circumferential direction. Moreover, because the first and second rotary plates 82a, 82b and the third and fourth rotary plates 87a, 87b are rotated asynchronously, the amount of deposition material Em adhering thereto can be further dispersed. Therefore, compared to when the deposition material Em adheres directly to the inner surface of the viewing window 7, the time until the light intensity decreases beyond the predetermined range can be significantly extended. As a result, the shutter 9 is provided to prevent the first to third imaging devices Is from being exposed to the light. １ ~Is ３ In addition to the fact that light can pass through the viewing window 7 only when the evaporation boat 3 is imaged, even when the third rotating plate 87a and the fourth rotating plate 87b of the second shielding part 8b are made of a relatively expensive material, it is possible to minimize increases in running costs.

[0028] Although the above describes an embodiment of the present invention, various modifications are possible without departing from the scope of the technical concept of the present invention. In the above embodiment, the deposition material Em is made of aluminum and a deposition boat is used for vacuum deposition. However, the present invention is not limited to this. The present invention can also be widely applied to vacuum processing using vacuum processing equipment such as sputtering equipment, ion plating equipment, and etching equipment, as long as it is necessary to monitor components in the vacuum chamber during vacuum processing in a vacuum atmosphere and the environment is such that contaminants may adhere to the observation window. Furthermore, the present invention is not limited to aluminum deposition material Em, but can also be applied to copper deposition material Em. Furthermore, while the deposition target is a sheet-shaped substrate Sw, the present invention can also be widely applied to film formation on substrates with a predetermined contour, such as glass or silicon wafers.

[0029] In the above embodiment, the first to third imaging devices Is are arranged so that the imaging positions of the deposition boat 3 are different and the imaging devices receive and capture light of different wavelength ranges. １ ~Is ３ However, the type and number of image capturing devices are not limited to this. For example, the first image capturing device Is may be a CCD camera that captures images by receiving visible light. １ In the case where only the first and second rotating plates 82a and 87b are provided, the second rotating plate 82b of the first shielding portion 8a and the fourth rotating plate 87b of the second shielding portion 8b are naturally omitted. Furthermore, in the above embodiment, the through holes 88a and 88b are described as slit-shaped, but the outline and number of the through holes are not limited to this. Furthermore, in the above embodiment, the third and fourth rotating plates 87a and 87b are described as the first shielding portion 8a, but the present invention is not limited to this.

[0030] As shown in Figure 4, in which the same components and parts as in the above embodiment are designated by the same reference numerals, in the shielding unit SU according to the modified example, instead of the first and second rotating plates 82a, 82b, the first shielding section 80 is constituted by a sheet-like member 80a that crosses in one direction behind the second shielding section 8b. Also, on the inner surface of the vacuum chamber sidewall 1b, a payout roller 102 positioned above the upper wall surface Hs1 and driven by a motor 101, and a take-up roller 104 positioned below the lower wall surface Hs2 and driven by a motor 103 are provided, and the sheet-like member 80a is wound around the payout roller 102 by a predetermined length. The first shielding section 80 is made of, for example, acrylic resin or polycarbonate, and its width is set to be equal to the width (diameter) of the observation window 7.

[0043] As a result, when the evaporation material Em adheres to the front surface of the sheet-like member 80a and the light intensity decreases, the sheet-like member 80a can be returned to its initial state simply by further unwinding it by a predetermined length, which is advantageous in that it reduces the frequency of replacing the second shielding part, which involves opening the vacuum chamber to the atmosphere. Note that in this modified example, the rear side of the second shielding part 8b, in other words, the entire rear surfaces of the third and fourth rotating plates 87a, 87b are covered. However, if the first rotating plate 82a and the second rotating plate 82b are made of different materials so as to transmit light of different wavelength ranges, for example, the fourth rotating plate 87b may be left in place, and the sheet-like member 80a may pass only behind the third rotating plate 87a.

[0031] 5, in which the same reference numerals are used for the same members and parts as in the above embodiment, in a shielding unit SU according to another modification, an inlet 111 and an outlet 112 for an inert gas such as nitrogen gas are provided on the upper wall surface Hs1 and the lower wall surface Hs2 adjacent to the front wall Hs3 of the storage chamber Hs, with the holes aligned with each other. A gas pipe 114 with a mass flow controller 113 is connected to the inlet 111, and the inert gas is supplied to each imaging device Is. １ ~Is ３ During the imaging of the deposition boat 3 by the microscope, a vertical gas flow (gas curtain) may be formed in front of the observation window 7 to serve as the first shielding part 8a. In this modification, the first rotating plate 82a and the second rotating plate 82b are installed as they are as the first shielding part, but they may be omitted depending on the vacuum treatment.

[0032] ES...vacuum deposition apparatus, SU...shielding unit, Em...wire-shaped deposition material, Em1...tip portion of the deposition material, Sw...sheet-shaped substrate (subject to deposition), 1...vacuum chamber, 3...deposition boat, 31...boat body, 31a...recess (portion for accommodating deposition material), 7...sight window, 8a...first shielding portion, 8b...second shielding portion, 82a...first rotating plate, 82b...second rotating plate, 83a, 83b...drive motors (driving means), 87a...third rotating plate, 87b...fourth rotating plate, 88a, 88b...slit-shaped through-holes, 9...shutter, 80a...sheet-shaped member.

Claims

1. A shielding unit that is installed in a vacuum chamber to prevent contaminants generated by vacuum processing from adhering to a sight glass installed in the wall of the vacuum chamber so that a predetermined amount of light in a predetermined wavelength range from components present in the vacuum chamber is transmitted through the sight glass while vacuum processing is being carried out in a vacuum chamber in a vacuum atmosphere, the shielding unit comprising: a first shielding part that is arranged in front of the sight glass and allows transmission of light in the predetermined wavelength range; and a second shielding part that is arranged in front of the first shielding part; the second shielding part is made of a plate-like member that has a plurality of through holes that penetrate in the front-to-rear direction along the circumferential direction; and a drive motor that rotates and drives the second shielding part.

2. The shielding unit according to claim 1, further comprising a shutter that can be opened and closed and is disposed in front of said second shielding portion.

3. A shielding unit as described in claim 1 or claim 2, characterized in that the first shielding section is composed of a plate-like member arranged in a row with a gap between it and the second shielding section in the front-to-back direction, and the second shielding section is rotated and driven asynchronously with the first shielding section.

4. A shielding unit as described in claim 1 or claim 2, characterized in that the first shielding section is composed of a sheet-like material that crosses the rear side of the second shielding section in one direction, and is provided with a pay-out roller that pays out the sheet-like material and a take-up roller that winds up the sheet-like material.

5. A vacuum deposition apparatus comprising the shielding unit of claim 1 or 2, further comprising a deposition boat having a storage section for deposition material placed in a vacuum chamber, and a material supply unit that supplies wire-shaped deposition material from above so as to abut against the bottom plate of the deposition boat that defines the storage section, and performing deposition on an object to be deposited in the vacuum chamber as the vacuum processing, wherein the vacuum deposition apparatus is provided with a plurality of imaging devices that receive light of a predetermined wavelength range from the deposition boat, which is a component present in the vacuum chamber, through the viewing window and capture images of various locations on the deposition boat, wherein the first shielding unit has a first rotation axis and a second rotation axis that are placed parallel to each other, and a first rotating plate and a second rotating plate that are extrapolated onto the first rotation axis and the second rotating axis, respectively, the second shielding unit has a third rotating plate that is extrapolated onto the first rotation axis with a reducer interposed therebetween, and a fourth rotating plate that is extrapolated onto the second rotation axis, and the first rotating plate and the second rotating plate are made of different materials corresponding to the wavelength range of light received by each imaging device.

Images