Alignment device, film forming apparatus, alignment method, and film forming method

Abstract

The present invention provides: an alignment device which is capable of shortening the distance between a substrate and a mask during an alignment operation; a film forming apparatus; an alignment method; and a film forming method.　The present invention specifically provides an alignment device which includes: an adjustment mechanism for adjusting the relative position of a wafer 21 and a mask 12 in a first direction that is parallel to a film formation surface of the wafer 21; and a transfer mechanism for relatively transferring the wafer 21 and the mask 12 in a second direction that intersects with the film formation surface. This alignment device is characterized in that adjustment by the adjustment mechanism is performed in a state where the distance in the second direction between the wafer 21 and the mask 12 is set at a prescribed distance that is defined on the basis of the position information at the time when the wafer 21 and the mask 12 are separated from each other from a state in which the wafer 21 and the mask 12 are in contact with each other by the transfer mechanism.

Description

Alignment apparatus, film formation apparatus, alignment method, and film formation method

[0001] The present invention relates to an alignment apparatus, a film forming apparatus, an alignment method, and a film forming method.

[0002] In the manufacture of organic electroluminescence displays and the like, a deposition material is deposited on a substrate using a mask. As a pre-processing step for deposition, the mask and the substrate are aligned and then superimposed. If the mask and the substrate are far apart during the alignment operation, the alignment accuracy may be reduced when the mask and the substrate are superimposed. Therefore, there is known a technique for detecting the relative distance between the mask and the substrate prior to the alignment operation and shortening the distance between the mask and the substrate during the alignment operation (see Patent Documents 1 and 2).

[0003] Japanese Patent No. 06814879 Japanese Patent Application Laid-Open No. 2022-57675

[0004] However, because the mask and substrate are subject to bending, it is difficult to shorten the relative distance between the mask and the substrate while taking the amount of bending into account. Patent Document 2 discloses a technology in which the substrate and the mask are separated based on position information when the substrate and the mask come into contact, and alignment is performed with the distance between the substrate and the mask shortened. While this technology can shorten the distance between the substrate and the mask during alignment, when the substrate and the mask are in contact, the portion of the mask that contacts the substrate is pushed by the substrate and bent. Because the amount of mask bending at this time cannot be detected, even if the substrate and the mask are separated by a predetermined distance to reliably separate the substrate and the mask from this state, the distance between the substrate and the mask may not be sufficiently shortened. Therefore, there is still room for improvement.

[0005] The present invention provides an alignment apparatus, a film deposition apparatus, an alignment method, and a film deposition method that can shorten the distance between a substrate and a mask during alignment operations.

[0006] The alignment device of the present invention comprises an adjustment mechanism that adjusts the relative position of the substrate and the mask in a first direction parallel to the film formation surface of the substrate, and a movement mechanism that moves the substrate and the mask relatively in a second direction intersecting the film formation surface, and is characterized in that the adjustment by the adjustment mechanism is performed in a state where the distance between the substrate and the mask in the second direction is set to a specified distance that is specified based on position information when the substrate and the mask are separated from a contact state by the movement mechanism.

[0007] A film formation apparatus of the present invention is characterized by comprising: the alignment apparatus; and a film formation source for forming a thin film on the film formation surface of the substrate.

[0008] The alignment method of the present invention is an alignment method that uses an adjustment mechanism to adjust the relative position of the substrate and the mask in a first direction parallel to the film formation surface of the substrate, and is characterized by having: a first step of using a movement mechanism to relatively move the substrate and the mask in a second direction intersecting the film formation surface so that the distance between the substrate and the mask in the second direction becomes a specified distance that is specified based on position information when the substrate and the mask are separated from a contact state by the movement mechanism; and a second step of adjusting the relative position of the substrate and the mask by the adjustment mechanism when the distance between the substrate and the mask in the second direction is the specified distance.

[0009] Furthermore, the film formation method of the present invention is characterized in that after the relative positions of the substrate and the mask are adjusted by the above alignment method, a thin film is formed on the film formation surface of the substrate using a film formation source.

[0010] As described above, according to the present invention, the distance between the substrate and the mask during the alignment operation can be shortened.

[0011] 1 is a schematic diagram of a film formation apparatus according to an embodiment of the present invention. FIG. 1 is an explanatory diagram of the operation ...2 is an explanatory diagram of the operation of a film formation apparatus according to an embodiment of the present invention. FIG. 3 is an explanatory diagram of the operation of a film formation apparatus according to an embodiment of the present invention. FIG. 4 is an explanatory diagram of the operation before an alignment operation according to a comparative example. FIG. 5 is an explanatory diagram of the operation before an alignment operation according to an embodiment of the present invention. FIG. 6 is an enlarged view of the periphery of the stage in FIG. 1. FIG. 7 is a top view of the stage. FIG. 8 is an arrangement diagram of wafer marks and mask marks. FIG. 9 is a flowchart showing an example of the overall operation of the film formation apparatus. FIG. 10 is a flowchart showing an example of the operation of mask rough alignment. FIG. 11 is a flowchart showing an example of the operation of wafer rough alignment. FIG. 12 is a flowchart showing an example of the operation of fine alignment. FIG. 13 is a flowchart showing an example of the operation of bringing a mask close to a wafer. FIG. 14 is an enlarged view of the periphery of the magnetic levitation stage when starting to bring the mask close to the wafer. FIG. 15 is an enlarged view of the periphery of the magnetic levitation stage when the mask and wafer are in contact. FIG. 16 is a diagram showing an example of the time response of a current value flowing through a voice coil built in a linear motor stator of the stage. FIG. 17 is a diagram showing an example of the time response of a current value flowing through a voice coil built in a linear motor stator of the stage. 10 is a diagram showing an example of the time response of the current value flowing through a voice coil built into the stator of the linear motor of the stage.

[0012] The following detailed description of the present invention will be given by way of example with reference to the accompanying drawings, although the dimensions, materials, shapes, relative positions, etc. of the components described in the examples are not intended to limit the scope of the present invention unless otherwise specified.

[0013] (Example) With reference to Figures 1 to 22, an alignment apparatus, a film deposition apparatus, an alignment method, and a film deposition method according to an example of the present invention will be described. For convenience, X, Y, and Z axes are shown in Figures 1, 9, 10, 17, and 18. The XY plane is a plane parallel to the film deposition surface of the substrate, and a direction parallel to this plane corresponds to the first direction. Furthermore, a direction parallel to the Z axis intersects with (here, is perpendicular to) the film deposition surface of the substrate. This direction parallel to the Z axis corresponds to the second direction.

[0014] <Overview of Film Forming Apparatus> An overview of a film forming apparatus including an alignment device according to this embodiment will be described with particular reference to FIG. 1 . FIG. 1 is a schematic diagram of a film forming apparatus 1 according to this embodiment, showing the configuration of the film forming apparatus 1 as viewed from the front. The film forming apparatus 1 is equipped with a magnetic levitation stage 2. The magnetic levitation stage 2 is fixed inside a vacuum chamber 4 via a stage support 3. The film forming apparatus 1 also includes a vibration isolation table 5 disposed on the top plate of the vacuum chamber 4 via a vibration isolation table base 6. A support frame 7 is supported on the vibration isolation table 5 to suppress vibrations transmitted from the vacuum chamber 4. A mask drive mechanism 8 placed on the support frame 7 can drive a mask support column 9 up and down. When the mask support column 9 is driven, a bellows 10 expands and contracts. The bellows 10 maintains the vacuum level within the chamber. The lower end of the mask support column 9 is disposed in the vacuum chamber 4 to support a mask table 11. A mask frame 13 with a mask 12 fixed thereto is carried in and placed on the mask table 11 by a robot hand (not shown) and a coarse movement stage (not shown). When the robot hand (not shown) and the coarse movement stage (not shown) move in and out to place the mask frame 13, the mask table 11 is lowered and retracted by a mask driving mechanism 8. An evaporation source 14 is installed below the mask 12 as a film formation source. In this embodiment, a vacuum evaporation apparatus will be described as an example of a film formation apparatus. In this case, the film formation source is an evaporation source. However, the film formation apparatus of the present invention can also be applied to, for example, a sputtering apparatus. In this case, the film formation source is a sputtering cathode.

[0015] The alignment camera 15 used for alignment is supported by the support frame 7. Supporting the alignment camera 15 by the support frame 7 also suppresses vibrations from the vacuum chamber 4, enabling high-precision measurements. A viewport 16 for alignment measurement is installed on the top plate of the vacuum chamber 4, allowing measurement of the inside of the vacuum chamber 4 from the atmospheric side. At least two alignment cameras 15 are installed to measure three axes around the X, Y, and Z directions. Here, an example in which two alignment cameras are installed will be described. The alignment cameras 15 are configured so that a fine camera with a narrow field of view but high accuracy and a rough camera with a wide field of view but low accuracy are installed close to each other, allowing for switching between the cameras to measure. The position within the field of view of the rough camera that will become the field of view of the fine camera is determined in advance by measuring a common measurement target. Furthermore, a configuration with a drive shaft that moves up and down to adjust the focal length of the alignment camera 15 can also be adopted.

[0016] The film forming apparatus 1 also has a control unit (not shown). The control unit has the function of controlling various mechanisms, the evaporation source 14, and film formation. The control unit can be configured, for example, by a computer having a processor, memory, storage, I / O, etc. In this case, the functions of the control unit are realized by the processor executing a program stored in the memory or storage. The computer may be a general-purpose personal computer, an embedded computer, or a PLC (programmable logic controller). Alternatively, some or all of the functions of the control unit may be configured by a circuit such as an ASIC or FPGA. A control unit may be provided for each film forming apparatus 1, or one control unit may control multiple film forming apparatuses 1.

[0017] <Overview of Operation of Film Forming Apparatus> An overview of the operation of the film forming apparatus 1 according to this embodiment (an overview of the operation from mask loading to film formation) will be described with particular reference to FIGS. 2 to 6 . FIGS. 2 to 6 schematically illustrate only the components necessary for describing the overview of the operation. Also, FIGS. 2 to 6 illustrate a coarse movement stage 30 for moving the mask 12 and the wafer 21 serving as a substrate. This coarse movement stage 30 is omitted from FIG. 1 . The coarse movement stage 30 includes a coarse movement stage support 31, a coarse movement stage support 32, and a movement mechanism 33 for moving these in the X direction, the Y direction, the Z direction, and a direction of rotation about an axis parallel to the Z direction (θ direction). It is well known that the movement mechanism 33 is configured by combining a mechanism for reciprocating various components, such as a ball screw mechanism or a rack-and-pinion mechanism, with a mechanism for rotating various components, such as a motor, and a detailed description thereof will be omitted.

[0018] First, the mask 12 is carried into the vacuum chamber by the robot hand 40 (see FIG. 2A) and placed on the coarse movement stage support 32 (see FIG. 2B). The robot hand 40 then retreats from the vacuum chamber, and rough mask alignment of the mask 12 is performed. The rough mask alignment is performed by moving and adjusting the coarse movement stage support 31 and the coarse movement stage support 32 in the X, Y, and θ directions. At this time, a rough camera is used as the alignment camera 15. FIG. 3A shows the relative positions of the various components when rough mask alignment is performed. After rough mask alignment is performed, the coarse movement stage support 31 and the coarse movement stage support 32 are lowered, and the mask 12 is placed on the mask table 11 (see FIG. 3B). The mask 12 placed on the mask table 11 is photographed by the alignment camera 15 to confirm that the mask 12 is placed within the desired range. If the mask 12 is not placed within the desired range, mask rough alignment is performed again, and the same operation is repeated until the mask 12 is placed within the desired range. After the mask 12 is placed on the mask table 11, the coarse movement stage support 31 rotates, and the coarse movement stage support part 32 retracts from the position below the mask frame 13 (FIG. 3C). Then, the coarse movement stage support 31 and the coarse movement stage support part 32 rise, and preparations for the operation of loading the wafer 21 begin.

[0019] Next, the wafer 21 is carried into the vacuum chamber by the robot hand 40 (see FIG. 4(a)) and placed on the coarse movement stage support part 32 (see FIG. 4(b)). Thereafter, the robot hand 40 retreats from the vacuum chamber, and wafer rough alignment of the wafer 21 is performed (see FIG. 4(c)). Wafer rough alignment is performed by moving and adjusting the coarse movement stage support 31 and the coarse movement stage support part 32 in the X direction, Y direction, and θ direction. At this time, a rough camera is used as the alignment camera 15.

[0020] When the wafer rough alignment is completed, the alignment camera 15 switches to a fine camera, and the wafer 21 is attracted to and held by the electrostatic chuck 20 serving as an attracting member (see FIG. 5(a)). Thereafter, the coarse movement stage support 32 retracts (see FIG. 5(b)), and the mask stage 11 is raised by the mask driving mechanism 8, and the mask 12 moves to a position close to the wafer 21 (see FIG. 5(c)). This step is the first step.

[0021] Then, with the distance between the mask 12 and the wafer 21 short (see FIG. 6A), fine alignment is performed. This is the second step. Fine alignment is performed by adjusting the movement of the electrostatic chuck 20 using the magnetic levitation stage 2. When this fine alignment is complete, the attraction magnet 24 is lowered by a mechanism (not shown), and the mask 12 is magnetically attracted and comes into close contact with the wafer 21 (see FIG. 6B). In this state, a thin film is formed on the wafer 21 via the mask 12 by the evaporation source 14.

[0022] <Preparatory Operations for Fine Alignment> The preparatory operations for performing fine alignment will now be described in more detail. As explained with reference to Figures 5(b) and 6(a), fine alignment is performed when the mask stage 11 is raised by the mask driving mechanism 8 and the mask 12 is moved to a position close to the wafer 21. The shorter the distance between the mask 12 and the wafer 21, the higher the alignment accuracy can be.

[0023] Therefore, by measuring in advance the position to which the mask table 11 should be raised in order to shorten the distance between the mask 12 and the wafer 21, it is possible to set the position to which the mask table 11 should be raised depending on the mask 12 being used. The method for this setting will be described below.

[0024] FIG. 7 shows a comparative example. In this comparative example, the mask 12 is raised (see arrow S1 in FIG. 7(a)), and the raising operation is stopped when the mask 12 contacts the wafer 21 (see FIG. 7(b)). FIG. 7(b) also shows an enlarged view of the vicinity of the contact portion between the mask 12 and the wafer 21. When the mask 12 contacts the wafer 21, the mask 12 is pressed against the wafer 21, causing the contact portion to bend. The dotted line in FIG. 7(b) indicates the shape of the mask 12 when not pressed against the wafer 21, and X in the figure corresponds to the amount of bending caused by being pressed against the wafer 21. There are individual differences in the mask 12, such as the amount of deformation when fixed to the mask frame 13, and the amount of bending X varies. Furthermore, this amount of bending X cannot be measured. Therefore, when moving the mask 12 away from the wafer 21 (see arrow S2 in FIG. 7C) to perform fine alignment, it is necessary to lower the mask 12 while taking into consideration the variation (error) in the amount of deflection X.

[0025] As described above, in this comparative example, the mask 12 must be lowered taking into consideration variations (errors) in the amount of flexure X, and therefore the mask 12 must be lowered with a certain amount of leeway in order to reliably separate the mask 12 from the wafer 21. Therefore, depending on the mask 12 used, the distance between the mask 12 and the wafer 21 may not be sufficiently short. Therefore, in this embodiment, a configuration is adopted in which the mask 12 and the wafer 21 are separated from each other without having to consider variations (errors) in the amount of flexure X, thereby making it possible to further shorten the distance between the mask 12 and the wafer 21.

[0026] 8 shows the setting method in this embodiment. In this embodiment, too, the mask 12 is first raised (see arrow T1 in FIG. 8(a)), and the raising operation is stopped when the mask 12 contacts the wafer 21 (see FIG. 8(b)). Then, in this embodiment, the mask 12 is lowered (see arrow T2 in FIG. 8(c)), and the lowering operation is stopped when the mask 12 separates from the wafer 21 (see FIG. 8(d)).

[0027] In this embodiment, the position of the mask 12 in the state shown in FIG. 8( d ) is used as the reference position, and the amount of movement required to move the mask 12 to a position close to the wafer 21 for fine alignment is determined. The above setting is performed for each mask 12 used. Note that if the mask 12 is placed at the reference position, the distance between the mask 12 and the wafer 21 will be too short. This may result in sliding between the mask 12 and the wafer 21 due to various errors, especially when the same mask 12 is used for the second or subsequent time. Therefore, fine alignment is performed with the mask 12 and the wafer 21 placed so that the distance between the mask 12 and the wafer 21 is longer by a predetermined clearance than when the mask 12 is placed at the reference position. The above clearance is set based on the dimensional tolerance of the wafer 21, errors in the amount of deflection deformation of the mask 12 and the wafer 21, and the like. In this embodiment, the variation (error) in the amount of deflection X in the comparative example does not need to be taken into consideration, and therefore the clearance can be set to a minimum. In this manner, in this embodiment, the distance (prescribed distance) between the mask 12 and the wafer 21 when fine alignment is performed is set in advance for each mask based on the information (position information) of the reference position. Then, fine alignment is performed with the mask 12 and the wafer 21 positioned so that the distance between them is the prescribed distance depending on the mask being used.

[0028] As described above, according to this embodiment, there is no need to take into account variations (errors) in the amount of deflection X, and therefore fine alignment can be performed more reliably when the distance between the mask 12 and the wafer 21 is short, compared to the comparative example.

[0029] The detailed configuration of the magnetic levitation stage 2 for performing fine alignment and a more specific example of the above setting method will be described below.

[0030] <Magnetic Levitation Stage> As shown in Figure 9, the magnetic levitation stage 2 has a movable part and a fixed part. The movable part consists of a stage frame 17, a plurality of gravity compensation magnet movers 18 installed on the stage frame 17, and a plurality of linear motor movers 19. An electrostatic chuck 20 is fixed to the stage frame 17, and is capable of holding a wafer 21, which is an object of film formation, by attracting it in a face-down position. The wafer 21 is also carried in by a robot hand (not shown) and a coarse movement stage (not shown), and is transferred to the electrostatic chuck 20. When the robot hand and the coarse movement stage move in and out to transfer the wafer 21, the mask stage 11 is also lowered and retracted by the mask driving mechanism 8.

[0031] The fixed portion of the magnetic levitation stage 2 is made up of a gravity compensation magnet stator 22 and a linear motor stator 23 that are fixed to the underside of the stage support 3 .

[0032] The moving part of the magnetic levitation stage 2 is supported by the stage support 3 due to the thrust generated between the weight compensation magnet mover 18 and the weight compensation magnet stator 22. This thrust is set to correspond to the weight of the moving part of the magnetic levitation stage 2. By changing the value of the current flowing through the voice coil built into the linear motor stator 23, the Lorentz force generated on the magnet built into the linear motor mover 19 can generate the required thrust. In the vertical direction, the weight of the moving part of the magnetic levitation stage 2 is canceled out by the weight compensation magnet mover 18 and the weight compensation magnet stator 22, as described above. Therefore, the current supplied to the voice coil built into the linear motor stator 23 is minimal, eliminating the risk of deformation or damage due to heat generation. If necessary, the voice coil built into the linear motor stator 23 can be covered with a water-cooled jacket and actively cooled by flowing a refrigerant through it.

[0033] FIG. 10 is a top view of the magnetic levitation stage 2. The relative positions of the linear motor movers 19 and linear motor stators 23, and the gravity compensation magnet movers 18 and gravity compensation magnet stators 22 will be described using FIG. 10 . The linear motor movers 19 are disposed at four corners on the upper surface of the stage frame 17. For convenience, the linear motor movers are denoted by reference numerals 19a, 19b, 19c, and 19d in FIG. 10 . The linear motor stators 23 are disposed on the lower surface of the opposing stage support 3 (not shown in FIG. 10 ). For convenience, the linear motor stators are denoted by reference numerals 23a, 23b, 23c, and 23d in FIG. 10 . Although simplified in the figure, each combination of the linear motor movers 19a, 19b, 19c, and 19d and the linear motor stators 23a, 23b, 23c, and 23d generates thrust in three directions: X, Y, and Z. Three voice coils are provided inside each of the linear motor stators 23a, 23b, 23c, and 23d to generate thrust in the three directions of X, Y, and Z. This makes it possible to drive the movable part of the magnetic levitation stage 2 with six degrees of freedom. For the sake of simplicity, the voice coils inside the linear motor stators 23a, 23b, 23c, and 23d below refer to voice coils that generate thrust in the Z direction unless otherwise specified.

[0034] Furthermore, the weight compensation magnet movers 18 are arranged at four locations symmetrically around the center of gravity. For convenience, the weight compensation magnet movers are indicated by the reference numerals 18a, 18b, 18c, and 18d in Fig. 10. The weight compensation magnet stator 22 is arranged on the underside of the opposing stage support 3. For convenience, the weight compensation magnet stators 22 are indicated by the reference numerals 22a, 22b, 22c, and 22d in Fig. 10. This allows the weight compensation magnet stators 22 to withstand moment forces as well, enabling stable levitation.

[0035] In this embodiment, four pairs of linear motor movers 19 and linear motor stators 23, and four pairs of gravity compensation magnet movers 18 and gravity compensation magnet stators 22 are provided, but at least three pairs are sufficient.

[0036] Here, the configuration around the magnetic levitation stage 2 will be described again with reference to Figure 9. The material of the mask 12 is, for example, a metal foil such as Invar that is resistant to thermal expansion, or a thin-film material such as a membrane film made by thinning a silicon wafer. As described above, the mask 12 is fixed to the mask frame 13, transported by the robot hand 40, and placed on the mask table 11 via a coarse adjustment stage (not shown). The mask 12 and mask frame 13 can be fixed, for example, by spot welding in a stretched state. Other methods such as mechanical clamping or adhesive fixation are also possible, and options include a method that minimizes distortion of the mask 12 during fixation.

[0037] The mask 12 contains a magnetic material within its surface and can be sucked up by an attraction magnet 24 that can move up and down relative to the magnetic levitation stage 2. The wafer 21 is held by the electrostatic chuck 20, but the attraction magnet 24 can approach a surface opposite the attraction surface of the electrostatic chuck 20 within a non-contact range and is configured to be able to generate the magnetic flux necessary to attract the mask 12. Because the electrostatic chuck 20 and the wafer 21 are made of non-magnetic materials, the magnetic flux of the attraction magnet 24 is formed up to the position of the mask 12, and an attraction force can be generated to move the mask 12 upward. As a result, the attraction force allows the mask 12 to come into contact with the wafer 21 and make tight contact. Ensuring close contact here makes it possible to prevent the film-forming material from getting around during film formation.

[0038] Furthermore, a plurality of through-holes corresponding to the pixel pattern are formed at equal intervals in the mask 12. In a vacuum environment, the film forming material evaporated from the evaporation source 14 heated to a high temperature passes through the through-holes in the mask 12 and is deposited on the surface of the wafer 21.

[0039] 11(a) is a diagram showing the layout of wafer marks, and FIG. 11(b) is a diagram showing the layout of mask marks. The wafer marks 25 and mask marks 26 will be explained using these figures. Wafer marks 25 are drawn on the wafer 21 for measuring the position with the alignment camera 15, and mask marks 26 are drawn on the mask 12. The number of wafer marks 25 and mask marks 26 drawn is equal to or greater than the number of alignment cameras 15. In this embodiment, there are two alignment cameras 15, and the wafer marks 25 and mask marks 26 are provided in two locations each.

[0040] 9, the peripheral configuration of the magnetic levitation stage 2 will be described. The attracting magnet 24 and the electrostatic chuck 20 have through holes in the areas that fall within the field of view of the alignment camera 15. This allows the alignment camera 15 to measure the wafer mark 25.

[0041] The sensor of the alignment camera 15 is preferably sensitive to infrared wavelengths, in which case it can measure the mask marks 26 by transmitting light through the wafer 21. To ensure mark contrast within the field of view and increase the mark recognition rate, it is desirable to install a light source 27 on the mask table 11, irradiate light from below the mask 12, and receive the light with the sensor of the alignment camera 15. In this case, through-holes are provided in the mask table 11 and mask frame 13, which are in the optical path of the light source 27. The through-holes in the attracting magnet 24, electrostatic chuck 20, mask table 11, and mask frame 13 may be filled with a light-transmitting material.

[0042] <Details of Alignment> Details of the relative positioning (alignment) of the wafer 21 and the mask 12 will now be described. As mentioned above, the thin film formed on the surface of the wafer 21 is determined by the positions of the through holes in the mask 12, so highly accurate alignment between the wafer 21 and the mask 12 is important. The relative positional relationship between the wafer 21 and the mask 12 is measured by the fine camera of the alignment camera 15 based on the amount of positional deviation between the wafer mark 25 and the mask mark 26. However, because it is difficult to increase the sampling frequency of the fine camera of the alignment camera 15, a laser displacement meter 28, which can increase the sampling frequency, is used to position the magnetic levitation stage 2.

[0043] The laser displacement meters 28 are installed on the mask stage 11 and measure the moving parts of the magnetic levitation stage 2. These laser displacement meters 28 are arranged in a total of six locations, at least two in the X direction, one in the Y direction, and three in the Z direction, enabling simultaneous measurement of the position with six degrees of freedom. Geometric coordinate transformation is then performed based on the six degrees of freedom information from the laser displacement meters 28, converting it into displacement and angular change around the center of gravity of the magnetic levitation stage 2. High-precision positioning is achieved by distributing thrust based on the results and driving each linear motor shown in FIG. 10. The coordinate transformation of the position information obtained from the laser displacement meters 28 and calculations to calculate thrust are performed by an apparatus control unit (not shown).

[0044] The laser displacement meter 28 is fixed near the mask 12 on the mask table 11, and is configured to be able to directly position the mask 12 and the magnetic levitation stage 2 in a vacuum environment without being affected by Abbe error or the like. Furthermore, the laser displacement meter 28 is able to perform stable measurements because vibrations from the chamber are suppressed by the vibration isolation table 5 on which the support frame 7 is placed via the mask table 11. On the other hand, the magnetic levitation stage 2 is supported by a gravity compensation magnet with low springiness, and vibrations from the chamber are similarly suppressed.

[0045] Furthermore, by using a highly rigid ceramic material for the material of the stage frame 17, a high natural frequency can be obtained, and the mechanical self-excited vibration that occurs when controlling the magnetic levitation stage 2 can be set to the high frequency side. This allows the feedback control loop using the laser displacement sensor 28 and each linear motor to have a high bandwidth, making it possible to significantly suppress disturbance vibrations.

[0046] These enable highly accurate positioning of the wafer 21 on the magnetic levitation stage 2 and the mask 12 placed on the mask table 11 relative to each other.

[0047] Next, an outline of an example of the overall operation related to alignment of the film forming apparatus 1 will be described. Fig. 12 is a flowchart showing an example of the overall operation related to alignment of the film forming apparatus 1. Here, this flowchart is performed with the inside of the vacuum chamber 4 in a vacuum environment.

[0048] In the following explanation, the word "step" will be omitted for each step, with step S1 simply referred to as S1 and step S2 simply referred to as S2. First, the mask 12 fixed to the mask frame 13 is carried in by a robot hand. Then, the mask 12 is positioned by a rough camera in the alignment camera 15 and then placed on the mask table 11. This step S1 will be referred to as mask rough alignment. Details of step S1 will be described later.

[0049] In S2, the wafer 21 is carried in by the robot hand 40. Then, the wafer 21 is positioned by the rough camera of the alignment camera 15, and then the wafer 21 is attracted to the electrostatic chuck 20. This S2 is referred to as wafer rough alignment. Details of S2 will be described later.

[0050] In S3, the mask 12 is brought close to the wafer 21. Details of S3 will also be described later.

[0051] In S4, the relative positional deviation between the mask 12 and the wafer 21 is measured by the fine camera of the alignment camera 15, and after adjustment to within specifications, the suction magnet 24 is activated to attract the mask 12, and the mask 12 and the wafer 21 are superimposed. This step S4 is referred to as fine alignment. Details of S4 will be described later.

[0052] In S5, the film forming material evaporated from the heated evaporation source 14 passes through the through-holes in the mask 12 and is deposited on the surface of the wafer 21. Note that even during deposition, the quality of the deposition is guaranteed by employing a configuration in which the amount of relative positional deviation between the mask 12 and the wafer 21 is measured by the fine camera of the alignment camera 15 to confirm the amount of positional deviation.

[0053] Details of S1, S2, and S4 will be explained below. After that, details of S3 will be explained.

[0054] First, the details of S1 will be described. Fig. 13 is a flowchart showing an example of the mask rough alignment operation in S1.

[0055] In S1-1, the mask stage 11 is lowered and retracted by the mask drive mechanism 8 to ensure a driving space between the robot hand and the coarse movement stage. In S1-2, the mask frame 13 to which the mask 12 is fixed is carried in by the robot hand. Then, in S1-3, the mask 12 is transferred from the robot hand to the coarse movement stage. At this time, the coarse movement stage positions the mask 11 so that two mask marks 26 in each of the fields of view of the two rough cameras in the alignment camera 15 are located within the field of view of the fine camera.

[0056] In S1-4, it is determined whether the two mask marks 26 in each of the fields of view of the two rough cameras in the alignment camera 15 are within the field of view of the fine camera. If they are not within the field of view, the process proceeds to S1-5, and if they are within the field of view, the process proceeds to S1-6.

[0057] In S1-5, the positioning operation by the coarse moving stage is performed again. The positioning by the coarse moving stage is repeated until the two mask marks 26 are positioned within the fields of view of the two rough cameras of the alignment camera 15, respectively, so that they are within the fields of view of the fine camera.

[0058] In S1-6, the mask 12 fixed to the mask frame 13 is placed on the mask table 11 by driving the coarse movement stage only in the Z-axis direction.

[0059] In S1-7, to check whether there was any misalignment when the mask 12 was placed on the mask table 11 in S1-6, it is determined whether the two mask marks 26 in each of the fields of view of the two rough cameras in the alignment camera 15 are within the field of view of the fine camera. If they are not within the fields of view, there was a misalignment when the mask 12 was placed, and the process proceeds to S1-8; if they are within the fields of view, the process proceeds to S1-9.

[0060] In S1-8, the coarse moving stage holds the mask 12 fixed to the mask frame 13 in order to reposition it, and then the process proceeds to S1-5 described above.

[0061] In S1-9, the mask rough alignment is completed, and the coarse adjustment stage is retracted.

[0062] Next, the details of S2 will be described. Fig. 14 is a flowchart showing an example of the wafer rough alignment operation in S2.

[0063] In S2-1, the wafer 21 is carried in by the robot hand 40. Then, in S2-2, the wafer 21 is transferred from the robot hand to the coarse movement stage. At this time, the coarse movement stage positions the wafer 21 to a position where two wafer marks 25 are within the fields of view of the two rough cameras in the alignment camera 15.

[0064] In S2-3, it is determined whether two wafer marks 25 are within the field of view of the two rough cameras in the alignment camera 15, respectively. If they are not within the field of view of the fine camera, the process proceeds to S2-4, and if they are within the field of view, the process proceeds to S2-5.

[0065] In S2-4, the positioning operation by the coarse adjustment stage is performed again. The positioning by the coarse adjustment stage is repeated until two wafer marks 25 in each of the fields of view of the two rough cameras of the alignment camera 15 are positioned within the field of view of the fine camera.

[0066] In S2-5, the wafer 21 is brought into contact with the electrostatic chuck 20 by being driven only in the Z-axis direction by the coarse movement stage. In S2-6, the electrostatic chuck 20 is activated, and the wafer 21 is attracted to the electrostatic chuck 20.

[0067] In S2-7, to check whether there is any misalignment when the wafer 21 is attracted to the electrostatic chuck 20 in S2-6, it is determined whether the two wafer marks 25 are within the field of view of each of the two fine cameras in the alignment camera 15. If they are not within the field of view, there is a misalignment during attraction, and the process proceeds to S2-8;

[0068] In S2-8, the coarse movement stage holds the wafer 21 so that it can be repositioned, and then the process proceeds to S2-4 described above.

[0069] In S2-9, since wafer rough alignment is completed, the coarse adjustment stage is retracted.

[0070] Next, the details of S4 will be described. Fig. 15 is a flowchart showing an example of the fine alignment operation in S4.

[0071] In S4-1, it is determined whether the relative positional deviation between the two wafer marks 25 and the mask mark 26 is within the standard range using each of the two fine cameras in the alignment camera 15. If it is not within the standard range, the process proceeds to S4-2, and if it is within the standard range, the process proceeds to S4-3.

[0072] In S4-2, the magnetic levitation stage 2 is driven to perform a positioning operation again, and the same operation is repeated until the relative positional deviation between the two wafer marks 25 and the mask mark 26 falls within the standard.

[0073] In S4-3, the attraction magnet 24 is activated to attract the mask 12 upward, bringing it into contact with and tightly fitting to the wafer 21. In S4-4, to check for any misalignment during the contacting process in S4-3, each of the two fine cameras in the alignment camera 15 determines whether the relative misalignment between the two wafer marks 25 and mask marks 26 is within specifications. If not, the process proceeds to S4-5; if yes, the fine alignment is complete.

[0074] In S4-5, in order to reposition the magnetic levitation stage 2, the attraction operation by the attraction magnet 24 is stopped and the mask 12 is peeled off from the wafer 21. Thereafter, the process proceeds to S4-2 described above, and the same operations are repeated.

[0075] Here, when the mask 12 is brought into close contact with the wafer 21 and superimposed in S4-3, misalignment may occur if the mask 12 and the wafer 21 are separated from each other. If there is an error in the parallelism between the mask 12 and the wafer 21, the alignment accuracy may decrease when they are superimposed.

[0076] Furthermore, if the mask 12 and the wafer 21 are in contact when the magnetic levitation stage 2 is driven in S4-2, the frictional force may cause the magnetic levitation stage 2 to oscillate, or the frictional force may damage the mask 12 and the wafer 21.

[0077] Therefore, S3, which brings the mask 12 and the wafer 21 as close as possible without contacting each other, becomes important.

[0078] However, the mask 12 has a thin structure so as not to interfere with the formation of a film of the evaporation material on the wafer 21. Residual stress during the manufacturing process of the mask 12 and the magnetic force of the attraction magnet 24 can cause the mask 12 to bend convexly toward the wafer 21. This bending of the mask 12 occurs when the mask 12, fixed to the mask frame 13, is placed on the mask table 11, making it difficult to determine the position and distance between the mask 12 and the wafer 21. Therefore, as explained in the comparative example above, in the past, the mask 12 and the wafer 21 had to be separated by a large distance to ensure that they did not come into contact with each other. In contrast, in this embodiment, as described above, it is possible to further shorten the distance between the mask 12 and the wafer 21 during the alignment operation.

[0079] The following describes in detail S3 of bringing the mask 12 close to the wafer 21. Fig. 16 is a flowchart showing an example of the operation of bringing the mask 12 close to the wafer 21 in S3.

[0080] In S3-1, the mask driving mechanism 8 is raised, bringing the mask 12 closer to the wafer 21. Figure 17 is an enlarged view of the periphery of the magnetic levitation stage 2 when the mask 12 begins to approach the wafer 21. As shown in this figure, the mask table 11 is lowered and retracted by the mask driving mechanism 8 in order to ensure a driving space for the robot hand that carries in the mask 12 and wafer 21 and the coarse adjustment stage. For ease of explanation, this figure exaggerates the deflection of the mask 12, but shows a state in which the mask 12 is deflected convexly toward the wafer 21.

[0081] In S3-2, when it is detected that the mask 12 has come into contact with the wafer 21, the upward movement of the mask driving mechanism 8 is terminated. Figure 18 is an enlarged view of the periphery of the magnetic levitation stage 2 when the mask 12 and wafer 21 are in contact. As shown in this figure, the mask 12 comes into contact with the wafer 21 at a location where there is bending.

[0082] A method for detecting contact between the mask 12 and the wafer 21 will now be described. FIG. 19 is a diagram showing an example of the time response of the current value flowing through the voice coil built into the linear motor stator 23 of the magnetic levitation stage 2 when contact between the mask 12 and the wafer 21 is detected. FIG. 19(a) shows the time response of the current value flowing through the voice coil built into the linear motor stator 23a. Similarly, FIG. 19(b) shows the current value of the voice coil built into the linear motor stator 23b, FIG. 19(c) shows the current value of the voice coil built into the linear motor stator 23c, and FIG. 19(d) shows the current value of the voice coil built into the linear motor stator 23d. In FIG. 19, the current value is the value when there is no contact and does not change until the mask 12 and the wafer 21 begin to come into contact. When the mask 12 and the wafer 21 begin to come into contact, a force due to the contact is applied to the magnetic levitation stage 2, but the magnetic levitation stage 2 is controlled to increase the current value to the linear motor stator 23 to maintain the commanded position. Therefore, as shown in the figure, the current value of the voice coil built in each of the linear motor stators 23a, 23b, 23c, and 23d increases.

[0083] Here, differences occur in the amount of increase in the current value of the voice coils built into each linear motor stator 23a, 23b, 23c, and 23d due to errors in the parallelism between the mask 12 and the wafer 21. Figure 19 shows a case where the distance between the mask 12 and the wafer 21 is closer on the side where the linear motor stator 23a is installed, and therefore the current value of the voice coil built into the linear motor stator 23a is larger than the current values ​​of the voice coils built into the other linear motor stators 23. From this increase in the current value of the voice coil built into the linear motor stator 23, contact between the mask 12 and the wafer 21 can be detected, and the parallelism between the mask 12 and the wafer 21 can also be detected.

[0084] In this embodiment, a configuration is adopted in which it is determined that the mask 12 and the wafer 21 have come into contact when it is detected that the current value of the voice coil built into the linear motor stator 23a, which has the largest increase, has increased to the upper limit of a predetermined standard range (S3-2).

[0085] In S3-3, only the combination of the linear motor mover 19 and linear motor stator 23 that has reached the upper limit of the current value specification range is driven in the direction separating the mask 12 and wafer 21. Driving continues until the current value of the linear motor stator 23 reaches the lower limit of the predetermined specification range. In this embodiment, only the combination of the linear motor mover 19a and linear motor stator 23a is driven. FIG. 20 shows an example of the time response of the current value flowing through the voice coil built into the linear motor stator 23 of the magnetic levitation stage 2 until the current value of the linear motor stator 23 reaches the lower limit of the predetermined specification range. This figure shows that the current value of the voice coil built into the linear motor stator 23a driven in the direction separating the mask 12 and wafer 21 has decreased to the lower limit of the predetermined specification range. At this time, the decrease in the current value of the voice coils built into the linear motor stators 23 other than the linear motor stator 23a is smaller than the decrease in the current value of the voice coil built into the linear motor stator 23a, and the difference in the amount of change in current value from when there is no contact for each linear motor stator 23 becomes smaller.

[0086] In S3-4, it is determined whether the amount of change in the current value flowing through the voice coils built into all linear motor stators 23 from when they are not in contact is between the lower limit and upper limit of the standard range. If it is not within the range, the process proceeds to S3-5, and if it is within the range, the process proceeds to S3-6. In the example shown in Figure 20, the current values ​​of the voice coils built into all linear motor stators 23 are not within the standard range, so the process proceeds to S3-5.

[0087] In S3-5, the magnetic levitation stage 2 is lowered to press the wafer 21 against the mask 12. Here, as in S3-1, the mask 12 may be pressed against the wafer 21 by raising the mask drive mechanism 8, but since the mask 12 and the wafer 21 are already in contact with each other, it is preferable to perform this using the magnetic levitation stage 2, which can be driven with higher precision.

[0088] Then, in S3-2, when it is detected that the current value of the voice coil built into the linear motor stator 23a has increased to the upper limit of the predetermined specification range, the descent of the magnetic levitation stage 2 is terminated. FIG. 21 is a diagram showing an example of the time response of the current value flowing through the voice coil until the current value of the linear motor stator 23 reaches the upper limit of the predetermined specification range again. Compared to FIG. 19, which shows the time response example of the first S3-2, the difference in the current value of the voice coil built into each linear motor stator 23 is smaller. The above operation is repeated in S3-4 until the amount of change in the current value flowing through the voice coil built into all linear motor stators 23 from the time of non-contact falls between the lower limit and the upper limit of the specification range. This allows the mask 12 and the wafer 21 to maintain a predetermined parallelism.

[0089] In S3-6, the mask driving mechanism 8 is lowered to separate the mask 12 from the wafer 21. Separation is determined when the current values ​​flowing through the voice coils built into all of the linear motor stators 23 drop to the non-contact value. At this point, the parallelism between the mask 12 and the wafer 21 is satisfied, and the part of the mask 12 closest to the wafer 21 and the wafer 21 are at the same position in the Z direction.

[0090] In S3-7, the mask driving mechanism 8 is lowered by the gap amount (clearance) between the mask 12 and the wafer 21 when the fine alignment in S4 is performed.

[0091] According to the above flowchart, the mask 12, which is warped and has insufficient flatness, can be adjusted to be parallel at a position with an arbitrary gap between it and the wafer 21, thereby enabling highly accurate alignment of the mask 12 and the wafer 21. This makes it possible to suppress misalignment between the mask 12 and the wafer 21 when they are closely superimposed, thereby achieving highly accurate deposition.

[0092] Note that if the above operation of S3 is performed for the mask 12 that is being used for the first time, it is possible to store position information for that mask 12 when the mask 12 is peeled from the contact state between the wafer 21 and the mask 12. Therefore, when using that mask for the second time or later, fine alignment can be performed by moving the mask to the position where fine alignment was performed the first time.

[0093] <Method for Manufacturing Electronic Device> Next, a description will be given of an example of a method for manufacturing an electronic device using the film forming apparatus 1 of this embodiment. Hereinafter, the configuration of an organic EL display device will be shown as an example of an electronic device, and a method for manufacturing the organic EL display device will be illustrated.

[0094] First, the organic EL display device to be manufactured will be described. Fig. 22(a) is an overall view of the organic EL display device 150, and Fig. 22(b) shows the cross-sectional structure of one pixel.

[0095] As shown in FIG. 22A , a display area 151 of an organic EL display device 150 includes a plurality of pixels 152 arranged in a matrix, each pixel including a plurality of light-emitting elements. As will be described in detail later, each light-emitting element has a structure including an organic layer sandwiched between a pair of electrodes. Note that the term "pixel" as used herein refers to the smallest unit capable of displaying a desired color in the display area 151. In the organic EL display device according to this embodiment, each pixel 152 is configured by a combination of a first light-emitting element 152R, a second light-emitting element 152G, and a third light-emitting element 152B, which emit light different from one another. While the pixel 152 is often configured by a combination of red, green, and blue light-emitting elements, it may also be configured by a combination of yellow, cyan, and white light-emitting elements, and is not particularly limited as long as it emits at least one color.

[0096] 22(b) is a partial cross-sectional schematic diagram taken along line A-B in FIG. 22(a). A pixel 152 is composed of a plurality of light-emitting elements, each of which has a first electrode (anode) 154, a hole transport layer 155, one of light-emitting layers 156R, 156G, or 156B, an electron transport layer 157, and a second electrode (cathode) 158 on a substrate 153. Of these, the hole transport layer 155, the light-emitting layers 156R, 156G, or 156B, and the electron transport layer 157 correspond to organic layers. In this embodiment, the light-emitting layer 156R is an organic EL layer that emits red light, the light-emitting layer 156G is an organic EL layer that emits green light, and the light-emitting layer 156B is an organic EL layer that emits blue light. The light-emitting layers 156R, 156G, and 156B are formed in patterns corresponding to the light-emitting elements (sometimes referred to as organic EL elements) that emit red, green, and blue light, respectively. Furthermore, the first electrode 154 is formed separately for each light-emitting element. The hole transport layer 155, the electron transport layer 157, and the second electrode 158 may be formed in common for the plurality of light-emitting elements 152R, 152G, and 152B, or may be formed for each light-emitting element. Note that an insulating layer 159 is provided between the first electrodes 154 to prevent short-circuiting between the first electrode 154 and the second electrode 158 due to foreign matter. Furthermore, since the organic EL layer deteriorates due to moisture and oxygen, a protective layer 140 is provided to protect the organic EL elements from moisture and oxygen.

[0097] 22(b), the hole transport layer 155 and the electron transport layer 157 are shown as a single layer, but depending on the structure of the organic EL display element, they may be formed of multiple layers including a hole blocking layer and an electron blocking layer. Furthermore, a hole injection layer having an energy band structure that can smoothly inject holes from the first electrode 154 to the hole transport layer 155 can be formed between the first electrode 154 and the hole transport layer 155. Similarly, an electron injection layer can be formed between the second electrode 158 and the electron transport layer 157.

[0098] Next, an example of a method for manufacturing an organic EL display device will be specifically described.

[0099] First, a circuit (not shown) for driving the organic EL display device and a substrate 153 on which a first electrode 154 is formed are prepared.

[0100] An acrylic resin is formed by spin coating on the substrate 153 on which the first electrode 154 is formed, and the acrylic resin is patterned by lithography so as to form an opening in the portion where the first electrode 154 is formed, thereby forming an insulating layer 159. This opening corresponds to the light-emitting region where the light-emitting element actually emits light.

[0101] The substrate 153 on which the insulating layer 159 has been patterned is carried into a first organic material film forming apparatus, and the substrate is held by a substrate support table and an electrostatic chuck. A hole transport layer 155 is formed as a common layer on the first electrode 154 in the display area. The hole transport layer 155 is formed by vacuum deposition. In practice, the hole transport layer 155 is formed to be larger than the display area 151, so a high-resolution mask is not required.

[0102] Next, the substrate 153 on which the hole transport layer 155 has been formed is carried into a second organic material film formation apparatus and held by a substrate support table and an electrostatic chuck. The substrate and a mask are aligned, and the substrate is placed on the mask. A red light-emitting layer 156R is then formed on the portion of the substrate 153 where the red light-emitting element is to be disposed.

[0103] Similar to the formation of the light-emitting layer 156R, a green-emitting light-emitting layer 156G is formed by a third organic material film formation apparatus, and then a blue-emitting light-emitting layer 156B is formed by a fourth organic material film formation apparatus. After the formation of the light-emitting layers 156R, 156G, and 156B is completed, an electron transport layer 157 is formed over the entire display region 151 by a fifth film formation apparatus. The electron transport layer 157 is formed as a layer common to the three light-emitting layers 156R, 156G, and 156B.

[0104] The substrate on which the electron transport layer 157 has been formed is moved in a metallic evaporation material deposition device, and a second electrode 158 is deposited.

[0105] Thereafter, the substrate is transferred to a plasma CVD device, where a protective layer 140 is formed, and the organic EL display device 150 is completed.

[0106] If the substrate 153 on which the insulating layer 159 has been patterned is exposed to an atmosphere containing moisture or oxygen from the time it is carried into the film-forming apparatus until the completion of the formation of the protective layer 140, the light-emitting layer made of the organic EL material may be deteriorated by the moisture or oxygen. Therefore, in this embodiment, the substrate is carried in and out of the film-forming apparatus in a vacuum atmosphere or an inert gas atmosphere.

[0107] (Summary) The film formation apparatus 1 according to this embodiment is provided with an adjustment mechanism that adjusts the relative position of the wafer 21 as a substrate and the mask 12 in a first direction (a direction parallel to the XY plane) parallel to the film formation surface of the wafer 21 as a substrate. In this embodiment, the coarse movement stage 30 corresponds to the adjustment mechanism in rough alignment. Furthermore, the magnetic levitation stage 2 corresponds to the adjustment mechanism in fine alignment. Thus, this embodiment employs a configuration that moves the wafer 21 as a substrate in order to adjust the relative position of the wafer 21 and the mask 12. However, in the present invention, the adjustment mechanism for adjusting the relative position of the substrate and the mask in the first direction may move the mask while the substrate is stationary, or may move both.

[0108] The film forming apparatus 1 also includes a movement mechanism that moves the wafer 21 and the mask 12 relatively in the second direction. The mask drive mechanism 8 that moves the mask 12 in the Z direction and the magnetic levitation stage 2 both correspond to the movement mechanism.

[0109] In this embodiment, adjustment (fine alignment) is performed by the adjustment mechanism in a state where the distance in the second direction between the wafer 21 and the mask 12 is set to a specified distance determined based on the positional information when the wafer 21 and the mask 12 are separated from each other by the moving mechanism from a contact state.

[0110] In addition, in this embodiment, a control unit is provided as a control means for controlling the movement mechanism so that the distance in the second direction between the wafer 21 and the mask 12 becomes the above-mentioned specified distance based on the position information stored according to the mask 12 being used.

[0111] The specified distance is specified based on the position information and the clearance (the deformation amount of the mask 12 in the second direction and the deformation amount of the wafer 21 in the second direction). That is, in S3-7 above, after the mask 12 and the wafer 21 are separated, in order to perform fine alignment, a configuration is adopted in which the mask driving mechanism 8 is lowered by a predetermined amount (gap amount (clearance)) to further separate the mask 12 from the wafer 21. As described above, if fine alignment is performed in the state in which it is detected that the mask 12 and the wafer 21 have been separated, the gap between them may be too narrow, causing the mask 12 and the wafer 21 to slide against each other. Furthermore, when the same mask 12 is used more than once, the operation of bringing the wafer 21 and the mask 12 into contact and then separating them is not performed. Therefore, depending on the dimensional tolerance of the wafer 21 and the state of the mask 12, the wafer 21 and the mask 12 may slide against each other. Therefore, a configuration is adopted in which the above-mentioned specified distance is determined taking into account a predetermined amount (gap amount) based on the deformation amount in the second direction of the mask 12 being used and the deformation amount in the second direction of the wafer 21.

[0112] In this embodiment, the movement mechanism has three or more drive mechanisms for moving either the wafer 21 or the mask 12. These drive mechanisms enable movement of either the wafer 21 or the mask 12 in the second direction and in a rotational direction around an arbitrary axis perpendicular to the second direction. More specifically, the magnetic levitation stage 2 serving as a movement mechanism has linear motor movers 19 and linear motor stators 23 at four locations as drive mechanisms for moving the wafer 21 using the electrostatic chuck 20. The drive mechanisms, consisting of the four linear motor movers 19 and linear motor stators 23, enable movement of the wafer 21 in the second direction (Z-axis direction) and in a rotational direction around an arbitrary axis perpendicular to the second direction. In other words, the multiple drive mechanisms enable control of the wafer 21 so that it tilts in any direction relative to the XY plane (a plane parallel to the horizontal plane in this embodiment). This allows adjustment of the parallelism of the wafer 21 and the mask 12. In this embodiment, a configuration for adjusting the tilt of the wafer 21, etc., is shown, but a configuration for adjusting the tilt of the mask 12 can also be adopted, or a configuration for adjusting the tilt of both.

[0113] Furthermore, as explained in S3 above, it is preferable that the above position information be information obtained when the parallelism between the wafer 21 and the mask 12 is within a predetermined range and the wafer 21 and the mask 12 are peeled off from a contact state.

[0114] This embodiment also includes a mask table 11 that holds the mask 12 and an electrostatic chuck 20 that serves as an attraction member that holds the wafer 21. As described above, the adjustment mechanism and the movement mechanism are mechanisms that move at least one of the mask table 11 and the electrostatic chuck 20.

[0115] Furthermore, in this embodiment, a detection means is provided that detects when the wafer 21 and the mask 12 transition from a separated state to a contact state, and when the wafer 21 and the mask 12 transition from a contact state to a separation state. As described in S3, this detection means detects contact and separation between the wafer 21 and the mask 12 based on changes in the current value of the voice coil built into the linear motor stator 23. That is, the detection means detects when the wafer 21 and the mask 12 transition from a separated state to a contact state, and when the wafer 21 and the mask 12 transition from a contact state to a separation state, based on measured values ​​of the control currents that control each of the multiple drive mechanisms. More specifically, the detection means detects the transition between the wafer 21 and the mask 12 from a separated state to a contact state when the control current begins to increase as the multiple drive mechanisms move the wafer 21 and the mask 12 toward each other. In addition, the detection means detects that the wafer 21 and the mask 12 have separated from each other when the above-mentioned control current downward state ends while the wafer 21 and the mask 12 are moving in the direction separating them by the multiple driving mechanisms.

[0116] The above position information is preferably information obtained when the multiple driving mechanisms are controlled so that the wafer 21 and the mask 12 separate after the values ​​of the control currents for all the driving mechanisms fall within a predetermined range (the range from the lower limit to the upper limit of the standard range shown in Figures 19 to 21), and the detection means detects that the wafer 21 and the mask 12 have transitioned from a contact state to a separated state.

[0117] 1: Film formation apparatus 2: Magnetic levitation stage 3: Stage support 4: Vacuum chamber 5: Vibration isolation table 6: Vibration isolation table base 7: Support frame 8: Mask drive mechanism 9: Mask support column 10: Bellows 11: Mask table 12: Mask 13: Mask frame 14: Evaporation source 15: Alignment camera 16: Viewport 17: Stage frame 18: Weight compensation magnet mover 19: Linear motor mover 20: Electrostatic chuck 21: Wafer 22: Weight compensation magnet stator 23: Linear motor stator 24: Attraction magnet 25: Wafer mark 26: Mask mark 27: Light source 28: Laser displacement meter 30: Coarse movement stage 31: Coarse movement stage column 32: Coarse movement stage support 33: Moving mechanism 40: Robot hand

Claims

1. An alignment device comprising: an adjustment mechanism that adjusts the relative position of the substrate and the mask in a first direction parallel to the deposition surface of the substrate; and a movement mechanism that moves the substrate and the mask relatively in a second direction intersecting the deposition surface, wherein the adjustment mechanism performs adjustment in a state in which the distance between the substrate and the mask in the second direction is set to a specified distance that is specified based on position information when the substrate and the mask are peeled off from a contact state by the movement mechanism.

2. An alignment apparatus as described in claim 1, characterized in that it is provided with a control means for controlling the moving mechanism so that the distance in the second direction between the substrate and the mask becomes the specified distance based on the position information stored according to the mask being used.

3. An alignment apparatus as described in claim 1 or 2, characterized in that the specified distance is specified based on the position information, the deformation amount in the second direction of the mask used, and the deformation amount in the second direction of the substrate.

4. An alignment device as described in claim 1 or 2, characterized in that the moving mechanism has three or more driving mechanisms for moving either the substrate or the mask, and these multiple driving mechanisms are configured to move either the substrate or the mask in the second direction and in a rotational direction rotating around an arbitrary axis perpendicular to the second direction.

5. An alignment apparatus as described in claim 1 or 2, characterized in that the position information is information obtained when the parallelism between the substrate and the mask is within a predetermined range and the substrate and the mask are peeled off from a contact state.

6. An alignment device as described in claim 1 or 2, characterized in that it comprises: a mask table that holds the mask; and an adsorption member that holds the substrate, and the adjustment mechanism and the moving mechanism are mechanisms for moving at least one of the mask table and the adsorption member.

7. An alignment apparatus as claimed in claim 1 or 2, further comprising a detection means for detecting a state in which the substrate and the mask have changed from a separated state to a contact state, and a state in which the substrate and the mask have changed from a contact state to a peeled state.

8. The alignment device according to claim 7, characterized in that the moving mechanism has three or more driving mechanisms for moving either the substrate or the mask, and the detection means detects a state in which the substrate and the mask have moved from a separated state to a contact state, and a state in which the substrate and the mask have moved from a contact state to a peeled state, based on the measured value of a control current that controls each of the multiple driving mechanisms.

9. The alignment device of claim 8, wherein the detection means detects the transition of the substrate and the mask from a separated state to a contacted state when the control current begins to rise as the substrate and the mask are moved toward each other by the multiple driving mechanisms, and detects the transition of the substrate and the mask from a contacted state to a separated state when the control current ends its decreasing state as the substrate and the mask are moved away from each other by the multiple driving mechanisms.

10. The alignment device described in claim 9, characterized in that the position information is information obtained when the multiple driving mechanisms are controlled so that the substrate and the mask separate after the values ​​of the control currents for all of the driving mechanisms fall within a predetermined range, and the detection means detects that the substrate and the mask have transitioned from a contact state to a separated state.

11. A film formation apparatus comprising: an alignment apparatus according to claim 1 or 2; and a film formation source for forming a thin film on the film formation surface of the substrate.

12. An alignment method for adjusting the relative position of the substrate and the mask in a first direction parallel to a film formation surface of the substrate using an adjustment mechanism, comprising: a first step of relatively moving the substrate and the mask in a second direction intersecting the film formation surface using a moving mechanism that relatively moves the substrate and the mask so that the distance in the second direction between the substrate and the mask becomes a specified distance that is specified based on position information when the substrate and the mask are peeled off from a contact state by the moving mechanism; and a second step of adjusting the relative position of the substrate and the mask by the adjustment mechanism when the distance in the second direction between the substrate and the mask becomes the specified distance.

13. A film formation method comprising the steps of: adjusting the relative positions of the substrate and the mask by the alignment method according to claim 12; and then forming a thin film on the film formation surface of the substrate using a film formation source.

Images