JP3575303B2 - Thin film formation method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a thin film forming method for forming a thin film on a film formation surface of a base such as a substrate by using a mask having a plurality of openings and transferring the shape of the openings of the mask. INDUSTRIAL APPLICATION This invention can be utilized, for example, when forming the thin film which comprises the electrode in display elements, such as an organic EL element.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there has been provided a thin film forming method in which a mask having a plurality of openings is used and a film formation process is performed on a film formation surface so as to transfer the shape of the openings of the mask.
[0003]
For example, in the formation of a thin film in an organic EL element, a film is formed by using a mask in which a plurality of slit openings having a fine width are juxtaposed and a bridge-like mask portion having a fine width is provided between adjacent slit openings. The shape of the slit opening of the mask is transferred to the film formation surface of the substrate, whereby a plurality of thin films having a fine width corresponding to the slit opening having a fine width are arranged in parallel to form a thin film for an electrode. I have decided.
[0004]
[Problems to be solved by the invention]
By the way, according to the above-described thin film forming method, it is not always easy to form a thin film in which the shape of the opening of the mask is transferred with high precision.
[0005]
In particular, when performing a film forming process using a mask in which a plurality of slit openings having a fine width are arranged in parallel and a bridge-shaped mask portion having a fine width is provided between adjacent slit openings, the slit opening and the bridge-shaped mask are used. Since both portions have a fine width (for example, about several tens of μm to several hundreds of μm), the rigidity of the bridge-shaped mask part tends to be insufficient, and a thin film in which the shape of the opening of the mask is transferred with high precision during the film forming process is formed. It is not always easy to do.
[0006]
The present invention has been made in view of the above circumstances, and it is a common object to provide a thin film forming method which is advantageous for forming a thin film in which the shape of a mask opening is transferred with high precision.
[0007]
[Means for Solving the Problems]
The thin film forming method according to the present invention uses a mask having a plurality of openings and a substrate having a surface on which a film is to be formed, and transfers the shape of the opening of the mask with the mask facing the surface on which the film is to be formed on the substrate. A thin film forming method of forming a thin film on a surface on which a film is to be formed,
The mask is an inner mask that faces the film-forming surface of the base and has a first group of openings formed of a plurality of first openings. An outer mask having a second opening formed in a number smaller than the number of one opening, and at least a double structure,
The inner mask is formed of a ferromagnetic material, the outer mask is formed of a paramagnetic or non-magnetic material,
In the film forming process, the second opening of the outer mask is opposed to the first opening of a part of the first opening group of the inner mask in a state where the inner mask is attracted to the film formation surface of the substrate by the magnetic attraction means. An operation for forming a film in a state where the outer mask is moved, and thereafter, the outer mask is moved so that the second opening of the outer mask faces the other first opening of the first group of openings of the inner mask. Operations to performSee
In the operation of forming a film, the inner mask is covered with an outer mask so as not to form a film in other first openings other than a part of the first openings in the first group of openings of the inner mask.It is characterized by the following.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
According to the method of the present invention, a mask having a plurality of openings and a substrate having a film-forming surface are used, and the shape of the opening of the mask is transferred while the mask faces the film-forming surface of the substrate. In this way, a thin film is formed on the surface of the substrate on which the film is to be formed.
[0009]
As a typical mask opening used in the method of the present invention, there is a slit opening elongated in one direction. A structure in which a plurality of slit openings are juxtaposed so as to be parallel to each other can be adopted. In this case, a bridge-like mask portion is provided between adjacent slit openings. The bridge-shaped mask portion can also be made narrow and elongated.
[0010]
According to the method of the present invention, the width of the slit opening can be made fine. The width of the slit opening is not particularly limited. For example, the upper limit can be set to 2000 μm, 1000 μm, and 100 μm, and the lower limit can be set to 1 μm and 5 μm. The width of the bridge-shaped mask portion can be made fine. The width of the bridge-shaped mask portion is not particularly limited. For example, the upper limit can be set to 2000 μm, 1000 μm, and 100 μm, and the lower limit can be set to 1 μm and 5 μm.
[0011]
As the film forming process according to the method of the present invention, a known film forming process can be adopted as long as a thin film can be formed on a film forming surface of a substrate through a mask. As a typical film forming process, there is a physical film forming method, and for example, a vacuum evaporation method, a sputtering method, an ion plating method and the like can be adopted. The thickness of the thin film to be formed can be appropriately selected depending on the application and the like, and can be several tens to several hundreds of nm, but is not limited thereto. The material of the thin film to be formed is not particularly limited. As the base, a substrate used for a display element such as an EL element can be employed..
[0012]
SuccessThe film processing is performed in a state where tension is applied to the mask so as to suppress the warpage and bending of the mask.Is preferred. MaSince tension is applied to the mask, the warpage and bending of the mask, especially the opening of the mask, are suppressed, thereby improving the transfer accuracy of the thin film..
[0013]
in this case,In general, a tension applying means for pulling a mask or a mask holder is used. As the tension applying means, a mechanical tension applying means or an electric tension applying means can be adopted. Examples of mechanical tension applying means include a method of applying tension to the mask using a screw pair, a method of applying tension to the mask using a fluid drive cylinder (a hydraulic cylinder, a pneumatic cylinder, etc.), and a gear mechanism. A method of applying tension to the mask by utilizing the method can be adopted. The electric tension applying means can be configured using a piezoelectric body that generates distortion due to voltage application, and a displacement magnifying mechanism that expands the distortion of the piezoelectric body and transmits it to a mask holder or a mask. Alternatively, the electric tension applying means can be configured using an ultrasonic motor and a transmission mechanism for transmitting the driving force of the ultrasonic motor to the mask holder or the mask..
[0014]
MaThe mask has at least a double structure including an inner mask and an outer mask, and the film forming process includes the step of causing the inner mask to face the surface on which the substrate is to be formed, and forming the inner mask on a surface of the inner mask facing away from the substrate. It is performed with the outer mask facing and the radiant heat to the inner mask is suppressed by the outer mask.. OutsideSince the radiant heat to the inner mask is suppressed by the mask, the inner mask on the side facing the film formation surface of the substrate can be prevented from being deformed due to thermal expansion, and the transfer accuracy of the thin film is improved..
[0015]
SuccessFilm treatment is performed by magnetic attraction meansInsidePerformed while the mask is magnetically attracted to the deposition surface of the substrate. InsideBecause the film is formed while the mask is magnetically attracted to the surface of the substrate on which the film is to be formed,InsideThe degree of fixation of the mask is secured, and the transfer accuracy of the thin film is improved..
[0016]
TeensAs typical magnetic air suction means, there is a method using an electromagnet or a method using a permanent magnet. Electromagnets can exert magnetic attraction with energization, and can eliminate magnetic attraction with the removal of residual magnetism due to power failure.InsideAdvantageous for suction or release of mask. InsideThe disc must be formed using a material that can be magnetically attracted. ThisExamples of such a material include an invar alloy (Fe-Ni-based) and an Fe-Pd alloy.. MagneticDue to the magnetic orientation effect based on the air suction means,InsideOne can also expect alignment of the bridge-like portions that define the openings in the mask.
[0017]
BookAccording to the method according to the invention, the mask is at least a double structure with an inner mask and an outer mask. The inner mask faces the surface on which the substrate is to be formed, and has a first opening group including a plurality of first openings. The first openings are preferably formed at equal pitch intervals. The outer mask is arranged on the surface of the inner mask facing away from the base, and has a second opening formed in a smaller number than the first openings of the inner mask. If the pitch interval between the first openings is Px and the pitch interval between the second openings is Py, Py = (Px · n). n is a numerical value of 2 or more, and is 2, 3, 4, 5, 6,.
[0018]
BookAccording to the method of the present invention, the film forming process is performed by performing a film forming operation in a state where the second opening of the outer mask faces the first opening of a part of the first group of openings of the inner mask, and Moving the outer mask to form a film with the second opening of the outer mask facing the other first opening of the first group of openings of the inner mask. Therefore, it is preferable to provide an inner mask fixing means for fixing the inner mask to the film formation surface of the substrate. As the inner mask fixing means, a method of mechanically fixing the inner mask can be adopted, or, when the inner mask is made of a material which can be magnetically attracted, the inner mask is formed on the substrate using magnetic attraction. A magnetic attraction method of adsorbing to a surface can be adopted.
[0019]
AlsoBookAccording to the method of the present invention, it is preferable to provide outer mask moving means for moving the outer mask. As the outer mask moving means, a method of moving with a motor, a method of moving with a fluid pressure cylinder, and a method of moving with an actuator can be adopted.
[0020]
【Example】
(referenceExample 1)
Hereinafter, according to the present inventionreferenceExample 1 will be described with reference to the drawings. FIG. 1 schematically shows a film forming apparatus.. SuccessThe film apparatus 1 includes a vacuum chamber 10 having a vacuum chamber 10a, a vacuum apparatus 11 such as a vacuum pump for increasing the vacuum chamber 10a to a high vacuum, a film forming source 12 held in the vacuum chamber 10a, and a film forming source 12. And a particle forming means 13 for causing the particles to fly toward a substrate as a base. The film forming source 12 includes a metal (Al) target 14 formed of a film forming material and a holding container 15 for holding the target.
[0021]
The particle forming means 13 includes a heater for heating the target 14, an electron beam generator for applying an electron beam to the target 14, and the like. The target 14 has a length LA close to the length of the mask 3. This is to ensure that particles from the target 14 can fly as perpendicular to the film-forming surface 6a of the substrate 6 as possible in order to ensure film-forming accuracy. The film forming apparatus 1 is provided with tension applying means 2 for applying a tension to the mask 3.
[0022]
FIG. 2 shows a schematic plan view of the mask 3. The mask 3 has a thin plate shape (thickness: about 100 to 500 m), and is provided between a plurality of slit openings 4 having a fine width arranged in parallel with each other and adjacent slit openings 4 so as to be parallel to each other. It has a plurality of bridge-shaped mask portions 5 arranged in parallel, a holding frame portion 33 provided around the slit opening 4, and a locked portion 34 having a through-hole shape penetrating in the thickness direction of the mask 3. The slit opening 4 and the bridge-shaped mask portion 5 extend along the arrow X1 direction.
[0023]
The width L1 of the slit opening 4 is several tens to several hundreds of micrometers, and the width L2 of the bridge-shaped mask portion 5 is several tens to several hundreds of micrometers, but is not limited thereto. In the present specification, “number” means 2 to 6.
[0024]
Since the width of the bridge-shaped mask portion 5 is small as described above, the rigidity is not always sufficient, and the bridge-shaped mask portion 5 tends to hang down even under its own weight.
[0025]
The mask 3 is formed by an etching process. The mask 3 is made of metal, specifically, an Invar alloy or stainless steel. As shown in FIG. 3, the through-hole locked portion 34 of the mask 3 is fitted and engaged with the protruding locking portion 18 of the mask holder 17. The mask holder 17 is mounted and supported on the holding portion 10r in the vacuum chamber 10a..
[0026]
SufferedA substrate 6 made of glass having a film forming surface 6a is used. Then, the substrate 6 is placed above the film forming source 12 with the film forming surface 6 a facing downward, and the film forming surface 6 a of the substrate 6 faces the film forming source 12. Similarly, the mask 3 is interposed between the substrate 6 and the film formation source 12, and the film formation surface 6 a of the substrate 6 is covered with the mask 3.
[0027]
In this state, the vacuum chamber 10a is evacuated to a high vacuum (10^-3-10^-6At the same time, the evaporated particles fly from the target 14 by the particle forming means 13 and are deposited on the surface 6a on which the substrate 6 is to be formed. Thus, a film forming process is performed through the mask 3. As a result, a plurality of thin films (target thickness: several to several hundred nm) are transferred to the deposition surface 6 a of the substrate 6. The thin films are arranged side by side so as to be parallel to each other, and have a strip shape having a fine width corresponding to the contour shape of the slit opening 4 of the mask 3..
[0028]
SuccessThe film processing is performed in a state where the mask 3 is pulled in the direction of the arrow X1 by applying tension and the tension along the direction of the arrow X1 is applied to the mask 3. Appropriate tension is applied so as not to pull too much. This suppresses the warpage and bending of the mask 3, so that even when the slit opening 4 and the bridge-like mask portion 5 of the mask 3 are narrow and narrow, the slit opening 4 and the bridge-like mask portion 5 are aligned with high precision. Thus, the transfer accuracy of the thin film is improved. The tension applying direction is the direction of the arrow X1 as described above, and is the direction in which the slit opening 4 and the bridge-shaped mask portion 5 extend.
[0029]
After the film forming process, the application of the tension by the tension applying means 2 is released, and the mask 3 is separated from the substrate 6.
[0030]
FIG. 3 schematically shows the tension applying means 2. The tension applying means 2 uses a screw pair as shown in FIG. With a screw pair, the rotational mobility can be converted to a linear motion.
[0031]
That is, the tension applying means 2 includes a screw shaft 22 having a male screw portion 21 held by a mask holder 17 holding the mask 3, an operation rotating body 25 having a female screw portion 24 screwed to the screw shaft 22, and an operation rotating body. 25 has a restricting portion 26 for preventing the screw shaft 22 from moving in the axial length direction, that is, in the direction of the arrow X1. If the operation rotator 25 is appropriately rotated in the circumferential direction, the screw shaft 22 is rotated in the axial direction while the operation rotator 25 is kept at a fixed position in the axial direction by screwing the female screw portion 24 and the male screw portion 21. That is, it moves along the arrow X1 direction. As a result, the mask holder 17 moves in the same direction while being guided by the holding portion 10r, whereby tension is applied to the mask 3.
[0032]
OperationSince the diameter D of the rotating member 25 is larger than the diameter of the screw shaft 22, it is advantageous for fine adjustment of the amount of movement for moving the mask holder 17 or the mask 3 in the direction of the arrow X1, and the tension applied to the mask 3 This is advantageous for fine adjustment of.
[0033]
FIG. 4 shows another embodiment. In this case, the tension applying means 2A includes an actuator 27 having a function of pulling the mask holder 17, and a drive circuit 28 for driving the actuator 27. By energizing the drive circuit 28, the actuator 27 is driven to pull the action portion 17k of the mask holder 17 along the arrow X1 direction to apply tension to the mask 3. The actuator 27 can be configured using an ultrasonic motor.
[0034]
(referenceExample 2)
Referring to FIG.referenceExample 2 will be described.referenceExample 2referenceThe configuration is basically the same as that of Example 1. Hereinafter, the description will be focused on the different parts.
[0035]
FigureAs shown in FIG. 5, the mask 3 'has a double structure including an inner mask 3A and an outer mask 3B. The inner mask 3A has a thin plate shape (thickness: several tens to several hundreds μm), and the outer mask 3B has a thin plate shape (thickness: several tens to several hundreds of μm). The inner mask 3A has slit openings 4A having a fine width and arranged side by side so as to be parallel to each other, and a bridge-shaped mask portion 5A provided between the slit openings 4A. The width L3 of the slit opening 4A is several tens to several hundreds μm. The width L4 of the bridge-shaped mask portion 5A is several tens to several hundreds μm.
[0036]
The outer mask 3B has substantially the same shape as the inner mask 3A. That is, the outer mask 3B has a thin plate shape, and has a slit opening 4B having a fine width arranged in parallel so as to be parallel to each other and a bridge-like mask portion 5B provided between the slit openings 4B. As shown in FIG. 5, the slit opening 4B of the outer mask 3B faces the slit opening 4A of the inner mask 3A. The bridge-shaped mask portion 5B of the outer mask 3B faces the bridge-shaped mask portion 5A of the inner mask 3A.
[0037]
The inner mask 3A and the outer mask 3B are each formed by an etching process. The inner mask 3A and the outer mask 3B are formed of an Invar alloy having a small coefficient of thermal expansion or stainless steel (austenitic, JIS-SUS304).
[0038]
In FIG. 5, the number of the slit openings 4A and 4B and the number of the bridge-shaped mask portions 5A and 5B are illustrated in a simplified manner, and the actual number is larger..
[0039]
InsideThe mask 3A faces the film-forming surface 6a of the substrate 6, and the surface 3A of the inner mask 3A that faces away from the substrate 6₀The inner mask 3A and the outer mask 3B are held by the mask holder 17 in a state where the outer mask 3B faces each other. The film forming process is performed in this state. In the film forming process, the vacuum chamber 10a is evacuated to a high vacuum (10^-3-10^-6At the same time, the vaporized particles are made to fly from the target 14 by the particle forming means 13 and are deposited on the film formation surface 6a of the substrate 6. Thus, a film forming process is performed through the mask 3 '. As a result, a plurality of thin films (target thickness: several to several hundred nm) are transferred to the deposition surface 6 a of the substrate 6.
[0040]
As described above, if the inner mask 3A for directly transferring the thin film is covered with the outer mask 3B during the film forming process, the radiation heat from the target 14 or the like is directly transmitted to the inner mask 3A. It is suppressed by. Therefore, deformation due to thermal expansion of the inner mask 3A can be suppressed. Therefore, during the film forming process, the degree of arrangement of the slit openings 4A of the inner mask 3A and the bridge-shaped mask portion 5A is easily maintained satisfactorily, and the transfer accuracy of the thin film is improved.
[0041]
FIG. 6 shows another embodiment. In this case, a spacer 27 is interposed between the inner mask 3A and the outer mask 3B. Therefore, the gap 38 (gap width: several tens to several hundreds μm) between the inner mask 3A and the outer mask 3B is reliably formed. The gap 38 can function as a heat transfer blocking space, and can suppress the heat of the outer mask 3B that has received the radiant heat being transferred to the inner mask 3A. Therefore, it is more advantageous to suppress deformation of the inner mask 3A due to thermal expansion, and can further contribute to higher precision of the thin film.
[0042]
Further, in this example, the width L6 of the bridge-like mask portion 5B of the outer mask 3B is smaller than the width L4 of the bridge-like mask portion 5A of the inner mask 3A. Since the transfer shape of the thin film is determined by the inner mask 3A, it is to ensure the transfer accuracy by the inner mask 3A.
[0043]
(referenceExample 3)
Referring to FIGS. 7 and 8referenceExample 3 will be described.referenceExample 3referenceThe configuration is basically the same as that of Example 1. Hereinafter, the different parts will be mainly described.
[0044]
The mask 3 has a small coefficient of thermal expansion and is formed of an invar alloy (Fe-Ni-based) which is also a magnetic material..
[0045]
BaseAn electromagnet device 7 functioning as magnetic air suction means is provided on the side of the plate 6 opposite to the film deposition surface 6a. The electromagnet device 7 is driven by a drive circuit 70. That is, when the electromagnet device 7 is energized by the drive circuit 70, the electromagnet device 7 exerts an exciting action, and the electromagnet device 70 exerts a magnetic attraction. When the electromagnet device 7 is cut off by the drive circuit 70, the electromagnet device 7 is demagnetized, and the magnetic attraction of the electromagnet device 7 basically disappears except for residual magnetism..
[0046]
SuccessIn the film processing, the magnetic attraction is exerted on the electromagnet device 7 so that the mask 3 is magnetically attracted to the film formation surface 6a of the substrate 6, whereby the mask 3 is brought into close contact with the film formation surface 6a of the substrate 6. In this case, the electromagnet device 7 is initially cut off, and after positioning the mask 3 on the film-forming surface 6a of the substrate 6, the electromagnet device 7 is energized to apply a magnetic attractive force. In this case, even when the bridge-shaped mask portion 5 of the mask 3 is narrow and narrow, it is advantageous to suppress the disorder of the arrangement of the bridge-shaped mask portion 5..
[0047]
MaSince the mask 3 is magnetically attracted to the film-forming surface 6a of the substrate 6 by the electromagnet device 7, the degree of fixation of the mask 3 during the film-forming process is increased. The fixed alignment degree of the narrow bridge-shaped mask portion 5 can be improved, and the transfer accuracy of the thin film can be improved.
[0048]
After the film formation, the electromagnet device 7 is turned off to eliminate its magnetic attraction. Then, as shown in FIG. 8, the mask 3 becomes free. Therefore, the mask 3 can be separated from the deposition surface 6a of the substrate 6.
[0049]
As in the embodiment shown in FIG. 9, a method in which the electromagnet device 7 has magnetic poles at one end 7a and the other end 7c in the thickness direction of the mask 3 can be adopted.
[0050]
Alternatively, it is also necessary to adopt a method of providing magnetic poles at one end 7d and the other end 7e in the direction along the length of the slit opening 4 of the mask 3 in the electromagnet device 7, as in the embodiment shown in FIG. Can be done according to
[0051]
Alternatively, as shown in FIG. 11, a method is employed in which the magnetic poles are provided on one end 7h and the other end 7i of the electromagnet device 7 in a direction intersecting the length direction of the slit opening 4 of the mask 3. You can do it as needed.
[0052]
(referenceExample 4)
Referring to FIG.referenceExample 4 will be described.referenceExample 4 describes each of the abovereferenceIt has each feature of the example. Ie bookreferenceIn the example, the mask 3 'has a double structure including an inner mask 3A and an outer mask 3B. The inner mask 3A has a thin plate shape, and includes a slit opening 4A having a fine width and a bridge-like mask portion 5A provided between the slit openings 4A.
[0053]
Said abovereferenceAs in the example, the outer mask 3B has substantially the same shape as the inner mask 3A. That is, the outer mask 3B has a thin plate shape, and has a slit opening 4B having a fine width and a bridge-like mask portion 5B having a fine width. A spacer 37 is interposed between the inner mask 3A and the outer mask 3B to form a gap 38.
[0054]
The inner mask 3A and the outer mask 3B are locked by locking portions 18 of a mask holder 17. The mask holder 17 is mounted on the holding part 10r.
[0055]
The mask holder 17 is pulled in the direction of arrow X1 by the tension applying means 2, and can apply an appropriate tension to the inner mask 3A and the outer mask 3B.
[0056]
ChangeTo the baseAn electromagnet device 7 is provided on the side of the plate 6 that faces away from the film formation surface 6a, and the inner mask 3A is attracted to the substrate 6 by the electromagnet device 7..
[0057]
ZhangAfter tension is applied to the inner mask 3A and the outer mask 3B by the force applying means 2, they are positioned. Thereafter, the electromagnet device 7 is energized to excite it. As a result, the inner mask 3A is attracted to the film formation surface 6a of the substrate 6. Therefore, even when the width of the bridge-shaped mask portion 5A of the inner mask 3A is as small as several μm to several tens of μm, the disorder of the arrangement of the bridge-shaped mask portion 5A and the bridge-shaped mask portion 5B can be effectively suppressed. . Therefore, it is advantageous for securing the transfer accuracy of the thin film.
[0058]
(ImplementationAn example)
Implemented with reference to FIGS.Exampleexplain. The mask 3 ″ according to this embodiment has a double structure including an inner mask 8 and an outer mask 9. The inner mask 8 has a small coefficient of thermal expansion and a magnetically attractable ferromagnetic material (for example, an Fe—Ni-based material). Alloy, Invar alloy).
[0059]
The inner mask 8 faces the film formation surface 6a of the substrate 6, and includes a first slit opening group 87 composed of a plurality of elongated first slit openings 80 (80a, 80b, 80c) arranged in parallel. Have. The first slit openings 80 are formed at equal pitch intervals.
[0060]
The outer masks 9 are arranged on the side of the surface of the inner mask 8 that faces away from the substrate 6, and are formed with a smaller number than the number of the first slit openings 80 of the inner mask 8 at uniform pitch intervals. It has a second slit opening group 97 formed by an elongated second slit opening 90.
[0061]
The outer mask 9 is formed of a paramagnetic material or a non-magnetic material having low magnetic attraction (for example, austenitic stainless steel, aluminum alloy, or the like).
[0062]
As shown in FIG. 14, if the pitch interval of the first slit openings 80 (80a, 80b, 80c) is Px, and the pitch interval of the second slit openings 90 is Py, Py = (Px · n). n is 3.
[0063]
Note that a gap 38 is formed between the outer mask 9 and the inner mask 8. The gap 38 can function as a heat transfer blocking space, and can further suppress heat transfer to the inner mask 8. An electromagnet device 7 for magnetically attracting the inner mask 8 is provided on the upper surface side of the substrate 6.
[0064]
In this embodiment, prior to the film forming process, the inner mask 8 is attracted to the film forming surface 6a of the substrate 6 by the electromagnet device 7 and fixed. Further, as shown in FIG. 14, the outer mask 9 is held on the side of the inner mask 8 facing the substrate 6. Thereby, as shown in FIG. 14, the second slit opening 90 of the outer mask 9 faces the first slit opening 80a of the first slit opening group 87 of the inner mask 8.
[0065]
The film forming process is performed in this state. Then, the thin film forming substance in the vacuum chamber passes through the second slit opening 90 of the outer mask 9 and the first slit opening 80a of the inner mask 8, and is deposited on the film formation surface 6a of the substrate 6, thereby forming the thin film 100a. . The thin film 100a has a shape obtained by transferring the first slit opening 80a of the inner mask 8. As can be understood from FIG. 14, the other first slit openings 80b and 80c are shielded by the outer mask 9, and no film is formed at this stage.
[0066]
Next, with the inner mask 8 fixed to the substrate 6, the outer mask 9 is moved in the direction of arrow K5 shown in FIG. In this case, the outer mask moving means 97 constituted by a motor mechanism is used. The moving distance is a distance corresponding to the pitch Px of the first slit openings 80 of the inner mask 8. As a result, the second slit opening 90 of the outer mask 9 faces the first slit opening 80b of the inner mask 8. Since the other first slit openings 80a and 80c are shielded by the outer mask 9, no film is formed at this stage. When the film forming process is performed in this state, the thin film forming substance passes through the second slit opening 90 of the outer mask 9 and the first slit opening 80b of the inner mask 8, and is deposited on the film formation surface 6a of the substrate 6, and 100b is formed. The thin film 100b has a shape obtained by transferring the first slit opening 80b of the inner mask 8.
[0067]
Next, with the inner mask 8 fixed to the substrate 6, the outer mask 9 is moved in the direction of arrow K5 shown in FIG. As described above, the moving distance is a distance corresponding to the pitch Px of the first slit openings 80 of the inner mask 8. As a result, the second slit opening 90 of the outer mask 9 faces the remaining first slit opening 80c of the inner mask 8. At this time, since the other first slit openings 80a and 80b are shielded by the outer mask 9, no film is formed at this stage. When the film forming process is performed in this state, the thin film forming substance passes through the second slit opening 90 of the outer mask 9 and the first slit opening 80c of the inner mask 8, and is deposited on the film formation surface 6a of the substrate 6, and 100c is formed. The thin film 100c has a shape obtained by transferring the first slit opening 80c of the inner mask 8. In this embodiment, the thin films 100a, 100b, and 100c are formed on the film formation surface 6a of the substrate 6 as described above.
[0068]
In this embodiment, since the outer mask 9 covers the inner mask 8 for directly transferring the thin films 100a, 100b, and 100c, the radiant heat from the target can be suppressed from being directly transmitted to the inner mask 8. Therefore, deformation of the inner mask 8 due to thermal expansion can be suppressed. This is advantageous for improving the transfer accuracy of the thin films 100a, 100b, 100c.
[0069]
Further, in this embodiment, although the outer mask 9 is moved during the film forming process, the inner mask 8 is fixed on the film forming surface 6a of the substrate 6, so that the inner mask 8 is formed on the film forming surface 6a of the substrate 6. Damage to the thin films 100a, 100b, 100c that are present can be suppressed. In this sense also, it is advantageous for improving the transfer accuracy of the thin films 100a, 100b, 100c.
[0070]
The number of the first slit openings 80 (80a, 80b, 80c) of the inner mask 8 is larger than the number of the second slit openings 90 of the outer mask 9, and is three times. Therefore, generally, although the outer mask 9 is advantageous for securing rigidity, the rigidity of the inner mask 8 tends to be lower than the rigidity of the outer mask 9. In this regard, in the present embodiment, the inner mask 8 that directly transfers the thin films 100a, 100b, and 100c but tends to have reduced rigidity can be supported from below by the outer mask 9 that is advantageous for securing rigidity. This is also advantageous for improving the transfer accuracy of the thin films 100a, 100b, 100c.
[0071]
In the present embodiment, the thin films 100a, 100b, 100c formed on the substrate 6 may be films formed of the same material. Alternatively, each of the thin films 100a, 100b, and 100c may be a film for three primary colors. For example, the thin film 100a may be a red (R) film, the thin film 100b may be a blue (B) film, and the thin film 100c may be a green (G) film.
[0072]
In the present embodiment, as shown in FIG. 15, when the slit width of the first slit opening 80 of the inner mask 8 is L7 and the slit width of the second slit opening 90 of the outer mask 9 is L8, L8 is larger than L7. It is set large. Therefore, the transfer accuracy of the thin film by the first slit opening 80 of the inner mask 8 is ensured.You.
[0073]
(Application example)
16 and 17 show application examples. This example is a case where the present invention is applied to the formation of a thin film in a spontaneous emission type organic EL (Elecro Luminescence) element. As shown in FIG. 16, a transparent electrode 60 (positive electrode, Indium Tin Oxide) as a microelectrode, a light emitting layer 61 having a light emitting function, and an electrode thin film as a microelectrode are provided on a transparent glass substrate 6. 52 (negative electrodes) are sequentially stacked.
[0074]
The electrode thin film 52 is formed of a conductive material, specifically, aluminum (Al). The luminous body layer 61 is configured by sequentially stacking a hole transport layer 65, an organic luminescent layer 66, and an electron transport layer 67 from the side close to the transparent electrode 60.
[0075]
Examples of the hole transport layer 65 include a tertiary amine derivative such as a triphenyldiamine derivative. As the organic light emitting layer 66, a substance known as a fluorescent dye can be adopted. Examples of the electron transport layer 67 include polysilane.
[0076]
As shown in FIG. 17, the transparent electrodes 60 are arranged side by side along the arrow Y1 direction. The electrode thin films 52 are juxtaposed in a direction crossing the transparent electrode 60, that is, along the direction of the arrow X1. Thereby, a matrix arrangement is formed.
[0077]
In this application example, the electrode thin film 52 (target thickness: several tens to several hundreds of nm) is formed by using the mask 3 as described above and forming a film through the mask 3.
[0078]
In some cases, the transparent electrode 60 (target thickness: several tens to several hundreds of nm) may be formed by using the mask 3 as described above and forming a film through the mask 3.
[0079]
【The invention's effect】
BookAccording to the method according to the present invention, since the outer mask covers the inner mask for directly transferring the thin film, the radiant heat during the film forming process can be suppressed from being directly transmitted to the inner mask, and the heat of the inner mask can be suppressed. Deformation can be suppressed, which is advantageous for improving the transfer accuracy of the thin film. Further, although the outer mask is moved during the film forming process, the inner mask remains facing the film forming surface of the substrate, so that it is possible to suppress damage to the thin film formed on the film forming surface of the substrate. This is more advantageous for improving the transfer accuracy of the thin film. Additionally, the number of first openings in the inner mask is greater than the number of second openings in the outer mask. Therefore, generally, although the outer mask is advantageous for securing rigidity, the rigidity of the inner mask tends to be lower than the rigidity of the outer mask. This pointBookAccording to the method of the present invention, the inner mask, which transfers the thin film directly but tends to have lower rigidity, can be supported from below by the outer mask, which is advantageous for securing the rigidity. It is advantageous for improvement of.
[Brief description of the drawings]
FIG.referenceFIG. 4 is a schematic configuration diagram illustrating a film formation mode according to Example 1.
FIG. 2 is a plan view of a mask.
FIG. 3 is a schematic configuration diagram showing a tension applying unit.
FIG. 4 is a schematic configuration diagram showing a tension applying unit according to another example.
FIG. 5referenceFIG. 9 is a schematic configuration diagram illustrating a film formation mode according to Example 2.
FIG. 6referenceFIG. 3 is a schematic configuration diagram illustrating a film formation mode according to an example.
FIG. 7referenceFIG. 13 is a schematic configuration diagram illustrating a form in which a mask is adsorbed to a substrate according to Example 3.
FIG. 8referenceFIG. 13 is a schematic configuration diagram illustrating a form according to Example 3 in which a mask is separated from a substrate.
FIG. 9 is a configuration diagram of an electromagnet device.
FIG. 10 is a configuration diagram of an electromagnet device having another magnetic pole arrangement.
FIG. 11 is a configuration diagram of an electromagnet device having still another magnetic pole arrangement.
FIG.referenceFIG. 9 is a schematic configuration diagram illustrating a film formation mode according to Example 4.
FIG. 13For exampleFIG. 4 is a perspective view showing a substrate, an inner mask, and an outer mask.
FIG. 14 is a sectional view showing a state where an inner mask and an outer mask are mounted on a substrate.
FIG. 15 is a cross-sectional view showing a main part in a state where an outer mask is applied to an inner mask.
FIG. 16 is a schematic cross-sectional view of an organic EL element according to an application example.
FIG. 17 is a schematic cross-sectional view showing a laminated structure of a transparent electrode, a light-emitting layer, and an electrode thin film in an organic EL device according to an application example.
[Explanation of symbols]
In the figure, 1 is a film forming apparatus, 2 is a tension applying means, 3 is a mask, 4A and 4B are slit openings, 5 is a bridge-like mask portion, 6 is a substrate (base), 6a is a film formation surface, and 3A is an inner surface. Reference numeral 3B denotes an outer mask, 37 denotes a spacer, 7 denotes an electromagnet device (magnetic attraction means).

Claims (1)

Using a mask having a plurality of openings and a substrate having a surface on which a film is to be formed, the substrate is formed such that the shape of the opening of the mask is transferred in a state where the mask faces the surface on which the film is to be formed on the substrate. A thin film forming method for forming a thin film on a film surface,
The mask is disposed on an inner mask facing the film-forming surface of the substrate and having a first opening group formed of a plurality of first openings, and a surface of the inner mask facing away from the substrate. An outer mask having a second opening formed in a number smaller than the number of the first openings of the inner mask, and
The inner mask is formed of a ferromagnetic material, the outer mask is formed of a paramagnetic material or a non-magnetic material,
In the film forming process, in a state where the inner mask is attracted to a film formation surface of the substrate by a magnetic attraction unit, the outer mask is partially inserted into the first opening group of the inner mask. An operation of forming a film with the second opening facing, and then moving the outer mask so that the second opening of the outer mask is moved to another first opening of the first group of openings of the inner mask. viewing including the operation and to form a film in a state of being face to face,
In the operation of performing the film formation, the inner mask is replaced with the outer mask so as not to form a film in other first openings other than a part of the first openings in the first group of openings of the inner mask. A method for forming a thin film, characterized by covering .

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