Sputtering device and sputtering method using the same

Abstract

One embodiment of the present disclosure discloses a sputtering device, comprising: a chamber, in which a sputtering object and a target are respectively installed; and a magnet part, which forms a magnetic field on the target and moves back and forth along a first direction, the magnet part has one or more unit magnets, the unit magnets include a central magnet extending along a second direction perpendicular to the first direction, and peripheral magnets surrounding the central magnet at predetermined intervals, the width of the central magnet at the end along the second direction is narrower than the central part of the body of the central magnet.

Description

Technical Field

[0001] The present disclosure relates to a sputtering device that utilizes a magnetic field to perform an evaporation operation and a sputtering method utilizing the same. Background Art

[0002] For example, thin film transistors used in display devices are manufactured by a deposition process using a magnetic field such as magnetron sputtering. That is, a prepared deposition target is sputtered using a magnetic field to form a thin film of a desired pattern on a display device substrate as a deposition target material. Summary of the invention

[0003] However, during the sputtering process, the target for evaporation may not be consumed uniformly as a whole, but may be consumed concentratedly in a specific part. This phenomenon occurs mainly because the plasma energy generated during sputtering is concentrated in a specific part. In this case, due to excessive consumption of a specific part, only the remaining target can be replaced in advance, which may have a significant negative impact on productivity.

[0004] Embodiments of the present disclosure provide a sputtering device and a sputtering method using the same, which are improved to prevent a specific portion of a target object from being over-consumed, thereby achieving a stable evaporation process.

[0005] An embodiment of the present disclosure provides a sputtering device, comprising: a chamber, in which a sputtering object and a target object are respectively installed; and a magnet part, which forms a magnetic field on the target object and moves back and forth along a first direction, the magnet part has one or more unit magnets, the unit magnets include a central magnet extending along a second direction perpendicular to the first direction, and peripheral magnets surrounding the central magnet at predetermined intervals, the width of the central magnet at the end along the second direction is narrower than the central part of the body of the central magnet.

[0006] The central portion of the body of the central magnet may have a constant width, and the width of the end portions may gradually narrow toward the outside along the second direction.

[0007] The width of the inner space of the peripheral magnet surrounding the central magnet may be narrower at the end portion in the second direction than at the center portion of the body of the central magnet.

[0008] It may be that the inner space of the peripheral magnet has a constant width at the center portion of the body of the central magnet, and the width of the inner space gradually narrows toward the outside along the second direction at the end portions.

[0009] The width of the inner space of the peripheral magnet may be stepped at the end and gradually narrowed.

[0010] It is possible that the width of the inner space of the peripheral magnet forms an inclination and continuously narrows at the end portion.

[0011] It is possible that the position where the width of the central magnet starts to narrow coincides with the position where the width of the inner space of the peripheral magnet starts to narrow along the second direction.

[0012] It is possible that the position where the width of the central magnet starts to narrow does not coincide with the position where the width of the inner space of the peripheral magnet starts to narrow along the second direction.

[0013] It is possible that a plurality of the unit magnets are arranged along the first direction. When the width of the peripheral magnet of each unit magnet is defined as t1, the interval between the end portions of adjacent peripheral magnets is defined as d1, the moving distance of each unit magnet in the first direction is defined as SL, and the interval between the central portions of the bodies of adjacent central magnets is defined as W, the relationship W = d1 + 3·t1 < SL is satisfied.

[0014] It is possible that during the evaporation deposition operation, a plasma having a shape corresponding to the interval between the central magnet and the peripheral magnet is formed between the object body and the target object.

[0015] Other aspects, features, and advantages other than the above will become clear from the following drawings, claims, and detailed description of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A front view schematically showing the structure of a sputtering device according to an embodiment of the present disclosure.

[0017] Figure 2 To show Figure 1 A top view showing the overlapping arrangement relationship of the magnet portion, the target object, the substrate, and the mask in the sputtering device shown in

[0018] Figure 3A To show Figure 1 A top view of the magnet portion in the sputtering device shown in

[0019] Figure 3B To show Figure 3A A top view of a comparative example of

[0020] Figure 4A To show the case of forming a plasma by the magnet portion of Figure 3A A perspective view of the case of forming a plasma by the magnet portion of

[0021] Figure 4B To show Figure 3B A perspective view of the case of forming a plasma by the magnet portion of

[0022] Figure 5 To show Figure 3A A top view of the specification conditions of the magnet portion shown in FIG.

[0023] FIG. 6A to FIG. 6D To show Figure 3A A top view of an example of a deformable magnet portion shown in FIG.

[0024] Figure 7 To show the use Figure 1 The sputtering device shown in FIG. 1 is a cross-sectional view of a target object that can be evaporated by a sputtering device, taking an organic light-emitting display device as an example. DETAILED DESCRIPTION

[0025] The present disclosure may be modified in various ways and may have various embodiments, of which specific embodiments are illustrated in the accompanying drawings and described in detail in the detailed description. Figure 1 However, the present disclosure is not limited to the following embodiments and can be implemented in various forms.

[0026] In the following embodiments, the terms "first" and "second" are not used for limitation but are used for the purpose of distinguishing one constituent element from another constituent element.

[0027] In the following embodiments, unless otherwise defined, an expression in the singular includes an expression in the plural.

[0028] In the following embodiments, the terms including or having mean that the features or constituent elements described in the specification exist, and do not preclude the possibility of adding one or more other features or constituent elements.

[0029] For the convenience of explanation, the size of the components may be enlarged or reduced in the drawings. For example, the size and thickness of each structure shown in the drawings are arbitrarily shown for the convenience of explanation, and the present disclosure is not necessarily limited to the drawings.

[0030] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the description with reference to the accompanying drawings, the same reference numerals are given to the same or corresponding components.

[0031] Figure 1 This is a front view schematically showing the structure of a sputtering device according to an embodiment of the present disclosure.

[0032] As shown in the figure, the sputtering device of this embodiment may include a chamber 200 and a magnet unit 100 . A substrate 10 and a vapor deposition target 20 as objects are arranged facing each other in the chamber 200 . The magnet unit 100 forms a magnetic field on the target 20 .

[0033] During sputtering, Figure 1 As shown, while argon gas is supplied into the chamber 200, discharge is induced with the target 20 as a cathode and the substrate 10 as an anode. At this time, argon ions are generated from the argon gas and plasma is formed. The argon ions of the plasma collide with the target 20 to scatter the particles of the target 20. The scattered particles pass through the pattern holes 31 of the mask 30 and are deposited on the substrate 10 to form a thin film. In addition, the magnet part 100 plays a role in forming a magnetic field to increase the sputtering speed due to the collision of the argon ions.

[0034] Here, the magnet unit 100 includes a plurality of unit magnets 110, each of which includes a central magnet 111 having an S pole and a peripheral magnet 112 having an N pole surrounding the central magnet 111. Figure 1 While moving back and forth in the X-axis direction (hereinafter also referred to as the first direction), the magnetic field is uniformly applied to the entire target object 20.

[0035] Figure 2 To show Figure 1 A top view of the overlapping arrangement relationship of the magnet unit 100, the target 20, the substrate 10, and the mask 30 in FIG.

[0036] from Figure 2 It can be seen that both the substrate 10 and the target 20 have a larger area than the pattern hole 31 of the mask 30 . Therefore, it can be considered that the edge portion outside the pattern hole 31 cannot be effectively used in the actual evaporation operation.

[0037] However, even so, if excessive consumption occurs at the edge of the target 20, the entire target 20 needs to be replaced. The reason is that if evaporation is continued when excessive consumption occurs and the edge is almost consumed, the equipment behind the target 20 may be directly damaged by heat, plasma, particles, etc.

[0038] However, in actual vapor deposition, the over-consumption phenomenon occurs almost always at the edge of the target object 20. This is because the shape of the plasma formed by the unit magnets 110 of the magnet unit 100 is formed in a shape that promotes the consumption of the edge of the target object 20.

[0039] Therefore, in this embodiment, in order to solve this problem, Figure 3A As shown, a magnet part 100 having an improved structure of a unit magnet 110 is provided.

[0040] As shown in the figure, a plurality of unit magnets 110 are arranged in the magnet portion 100 , and the unit magnets 110 have the same structure.

[0041] Observing one of the unit magnets 110 , the unit magnet 110 includes a central magnet 111 with an S pole extending in the Y direction (hereinafter also referred to as the second direction) in the figure and a peripheral magnet 112 with an N pole surrounding the central magnet 111 , and a gap exists between the central magnet 111 and the peripheral magnet 112 .

[0042] Furthermore, the center portion of the main body of the center magnet 111 has the same width, but the widths of the two side ends 111 a become narrower toward the outside.

[0043] The inner space 110a of the outer magnet 112 surrounding the central magnet 111 has the same width at a position corresponding to the center of the body of the central magnet 111, but the width of the inner space 110a at both side ends 112a becomes narrower toward the outside.

[0044] That is, the center magnet 111 and the peripheral magnet 112 are extended along the Y direction perpendicular to the X direction in which the magnet unit 100 reciprocates, and are configured to be narrower at both side ends 111a and 112a than at the center.

[0045] This is a measure for preventing the edge of the target 20 from being excessively consumed as described above. To illustrate this effect, the following will be described together. Figure 3B The side end portions 111a' and 112a' shown in the figure are also configured with the same width as the central portion. Figure 3B In the magnet portion 100' of the comparative example, the central magnet 111' and the peripheral magnet 112' are configured to extend in the Y direction to both side ends without changing their widths.

[0046] This Figure 3A The structure of the magnet part 100 of this embodiment is Figure 3B The difference in the structure of the magnet part 100' of the comparative example induces a difference in the shape of the plasma generated during the vapor deposition. That is, since the plasma formed between the target 20 and the substrate 10 is formed in a shape corresponding to the shape of the interval between the central magnet 111, 111' and the peripheral magnet 112, 112', as described above, if the shape of the central magnet 111, 111' and the peripheral magnet 112, 112' changes, the shape of the plasma also changes.

[0047] Figure 4A Shown by Figure 3A The structure of the magnet part 100 of this embodiment forms a plasma 40 between the target 20 and the substrate 10. Figure 4B Shown by Figure 3B The structure of the magnet unit 100 ′ of the comparative example forms a plasma 40 ′ between the target 20 and the substrate 10 .

[0048] Here, it can be seen that the plasma is formed in a shape corresponding to the shape of the interval between the central magnets 111, 111' and the peripheral magnets 112, 112', and thus the shapes of the A and A' portions as the end portions are formed differently. Figure 4A In the comparative example, the tip A of the plasma 40 is formed in a sharp shape. Figure 4B In the embodiment, the end portion A' of the plasma 40' is formed in a shape extending in the X direction. Such a difference determines whether or not excessive consumption occurs at the end portion of the target 20 in the Y direction.

[0049] That is to say, Figure 4A In the structure of , since the end portion A of the plasma 40 is sharp, there is no portion that is always located in the plasma 40 region when the unit magnet 110 moves back and forth in the X direction. Figure 4A In the embodiment, the end portion A of the plasma 40 is similar to a straight line extending in the Y direction, and when the straight line moves back and forth in the X direction, the part of the target 20 overlapping with the straight line will change constantly. Therefore, the phenomenon of concentrated consumption of a specific part will not occur.

[0050] However, in Figure 4B In the comparative example in which the end portion A' of the plasma 40' is elongated in the X direction, when the unit magnet 110' moves back and forth in the X direction, the portion of the target 20 corresponding to the end portion A' of the plasma 40' is exposed to the plasma 40' for a much longer time than other portions. In an extreme case, when the reciprocating distance of the unit magnet 110' in the X direction is shorter than the length of the end portion A' in the X direction, exposed portions may still appear under the influence of the plasma 40' during the entire evaporation operation. In this case, the consumption of the portion exposed to the plasma 40' for a longer time will be relatively very serious. Therefore, even if there is sufficient target 20 remaining in other portions, the entire target 20 should be replaced in order to prevent damage to other equipment due to the excessively consumed portion.

[0051] On the contrary, Figure 4A In the present embodiment, as described above, the central magnet 111 and the peripheral magnet 112 of the unit magnet 110 are configured so that the end portion A of the plasma 40 becomes a sharp shape. Therefore, when the unit magnet 110 moves back and forth in the X direction, the portion exposed to the plasma 40 changes constantly, so that the phenomenon of concentrated consumption at a specific portion does not occur. In addition, due to the difference in the structure of the ends of the unit magnets 110 and 110', the magnetic field strength will also be different. When the magnetic field strength is actually measured, it can be confirmed that Figure 3A and Figure 4AThe magnetic field intensity at the end of the unit magnet 110 shown in Figure 3B and Figure 4B is reduced compared to the magnetic field intensity at the end of the unit magnet 110' in the comparative example.

[0052] Therefore, if the magnet part 100 having the structure shown in Figure 3A and Figure 4A is adopted, it is possible to prevent the phenomenon that a specific part of the target 20 is excessively consumed, and thus it is possible to smoothly eliminate problems such as early replacement of the target 20 that is disadvantageous to productivity.

[0053] On the other hand, as described above, it is a problem that there is a part of the target 20 that is exposed to the plasma 40 for a relatively long time, but conversely, it is also difficult that there is a part of the target 20 that is not exposed to the plasma 40 at all. If so, an unconsumed part that does not contribute to the vapor deposition at all will be generated in the target 20, and this unconsumed part may act as another pollution source. For example, a phenomenon called redeposition may occur in which fine particles scattered from the target 20 by the plasma 40 adhere to this unconsumed part, and a vicious cycle may occur in which the part where the redeposition occurs acts as a pollution source that hinders precise vapor deposition. Especially in this embodiment, both end portions of the unit magnet 110 are formed in a shape with a narrowed width, so the interval between adjacent unit magnets 110 becomes relatively farther at both end portions than at the central portion. Thus, if the round-trip movement distance is set only considering the central portion of the unit magnet 110, an area not exposed to the plasma 40 may still be formed at both end portions.

[0054] Figure 5 The conditions for preventing unconsumed parts from being generated at both end portions of the target 20 are shown. When the width of the peripheral magnet 112 of each unit magnet 110 is defined as t1, the interval between the end portions of adjacent peripheral magnets 112 is defined as d1, the movement distance of each unit magnet 110 in the X direction (first direction) is defined as SL, and the interval between the central portions of the bodies of adjacent central magnets 111 is defined as W, the relationship of W = d1 + 3·t1 < SL is satisfied.

[0055] If so, even if the widths of both end portions of the unit magnet 110 are manufactured in a narrow manner, unconsumed parts of the target 20 not exposed to the plasma 40 will not be generated.

[0056] Before describing the sputtering process using the sputtering device as described above, as an example of an object on which a thin film can be vapor-deposited by this sputtering device, refer to Figure 7 to briefly describe the structure of the display device 300.

[0057] As Figure 7As shown, the display device 300 includes a thin film transistor 310 and an organic light emitting element 320 .

[0058] First, the organic light emitting element 320 is driven by the thin film transistor 310 to emit light, thereby forming an image. The organic light emitting element 320 includes a pixel electrode 321 and a counter electrode 323 facing each other, and a light emitting layer 322 arranged between the pixel electrode 321 and the counter electrode 323 .

[0059] A constant voltage is always applied to the counter electrode 323, and a voltage is selectively applied to the pixel electrode 321 connected to the thin film transistor 310 through the thin film transistor 310. Therefore, according to the selective voltage application of the thin film transistor 310, if an appropriate voltage is formed between the two electrodes (the pixel electrode 321 and the counter electrode 323), the light-emitting layer 322 between the pixel electrode 321 and the counter electrode 323 emits light, and an image is formed.

[0060] Furthermore, the thin film transistor 310 is configured such that an active layer 316, a gate electrode 317, a source electrode 318, and a drain electrode 319 are sequentially stacked on a substrate 330. Therefore, when an electric signal is applied to the gate electrode 317, electricity can be supplied from the source electrode 318 to the drain electrode 319 through the active layer 316, thereby applying a voltage to the pixel electrode 321 connected to the drain electrode 319, thereby inducing the light emission of the light emitting layer 322 as described above.

[0061] Reference numeral 311 denotes a buffer layer between the substrate 330 and the active layer 316 , reference numeral 312 denotes a gate insulating layer, reference numeral 313 denotes an interlayer insulating film, reference numeral 314 denotes a passivation film, and reference numeral 315 denotes a pixel definition film.

[0062] For reference, in the organic light-emitting element 320, a hole injection layer (HIL), a hole transport layer (HTL), an electron transport layer (ETL), an electron injection layer (EIL), etc. may be stacked adjacent to the light-emitting layer 322. In addition, each pixel of the light-emitting layer 322 is formed separately, so that pixels emitting red, green, and blue light are gathered to form a unit pixel. Alternatively, the light-emitting layer 322 may be formed in common through the entire pixel area regardless of the position of the pixel. In this case, the light-emitting layer 322 may be formed by vertically stacking or mixing layers of, for example, light-emitting materials that emit red, green, and blue light. Of course, if white light can be emitted, other colors can be combined. In addition, a color-changing layer or a color filter that converts the emitted white light into a predetermined color may also be provided. In addition, a thin film encapsulation layer (not shown) in which organic films and inorganic films are alternately stacked may be formed on the counter electrode 323.

[0063] In this structure, the sputtering device can be used when forming various conductive layers of the thin film transistor 310. For example, when forming the gate electrode 317 of Mo material, the source electrode 318 and the drain electrode 319 of Ti / Al / Ti material, the active layer 316 of TiN and IZO material, etc., if the sputtering device with the above-mentioned magnet part 100 is used, the evaporation operation can be smoothly performed without frequently replacing the target object 20. At this time, it can be considered that the substrate 330 of the display device 300 is equivalent to being installed on Figure 1 The substrate 10 is placed in the chamber 200 .

[0064] The sputtering device can be used as follows.

[0065] First, if Figure 1 As shown, a substrate 10 as a target object to be subjected to vapor deposition and a target 20 as a vapor deposition source are respectively installed in a chamber 200 .

[0066] The magnet unit 100 is located outside the chamber 200 at a position close to the target object 20 and reciprocates while preparing to start vapor deposition.

[0067] In this state, argon gas is injected into the chamber 200 , and voltage is applied to the target 20 and the substrate 10 , thereby performing sputtering while forming the plasma 40 .

[0068] The magnet unit 100 is along Figure 1 The magnetic field is moved back and forth in the X direction so that a uniform magnetic field acts on the target object 20.

[0069] At this time, if Figure 4A As shown, at both ends of the target 20 in the Y direction, the plasma 40 is formed in a sharp shape, so that excessive consumption does not occur at a specific location, thereby eliminating the problem of early replacement of the target 20, and if the following conditions are met: Figure 5 If the specification conditions are met, no unconsumed portion of the target object 20 will be generated. Thus, the vapor deposition operation can be stabilized and productivity can be improved.

[0070] In addition, the ends of each unit magnet 110 of the magnet unit 100 can be deformed into various shapes. That is, the width of the central magnet 111 and the width of the inner space 110a of the peripheral magnet 112 are basically the same, and the shapes are narrower at both ends than at the center, but can be deformed into more shapes.

[0071] first, Fig. 6A The structure described above is shown as it is, and the end 111a of the center magnet 111 is in a shape in which the width continuously narrows, and the end 112a of the peripheral magnet 112 is also configured to be inclined and the internal space 110a is in a shape in which the width continuously narrows.

[0072] However, if Figure 6B As shown, the central magnet 111 has the same shape, while the end 112a of the peripheral magnet 112 can be deformed into a stepped shape that gradually narrows.

[0073] And, in Fig. 6A and Figure 6B The example in FIG. 1 shows a structure in which the position where the central magnet 111 starts to narrow and the position where the inner space 110a of the peripheral magnet 112 starts to narrow are actually the same. Figure 6C and Fig.6D As shown, the position where the central magnet 111 starts to narrow and the position where the inner space 110a of the peripheral magnet 112 starts to narrow may not coincide. In other words, even if the central magnet 111 and the peripheral magnet 112 do not necessarily start to narrow at the same position, a similar effect can be expected.

[0074] Therefore, by using a sputtering device with such a structure, it is possible to prevent a specific portion of the vapor deposition target from being excessively consumed, thereby eliminating problems such as early replacement of the target, thereby stabilizing the vapor deposition operation and improving productivity.

[0075] As described above, the present disclosure is described with reference to an embodiment shown in the accompanying drawings, but this is only exemplary, and a person skilled in the art should understand that various modifications and variations of the embodiments can be made therefrom. Therefore, the true technical protection scope of the present disclosure should be defined according to the technical ideas of the claims.

Claims

1. A sputtering device, wherein: The sputtering device includes: a chamber in which a sputtering object and a target are respectively installed; and a magnet part that forms a magnetic field in the target and reciprocates along a first direction, the magnet part includes one or more unit magnets, and each unit magnet includes a central magnet extending along a second direction perpendicular to the first direction, and an outer magnet surrounding the central magnet at a predetermined interval, the width of the end of the central magnet along the second direction is narrower than the central part of the body of the central magnet, a plurality of the unit magnets are arranged along the first direction, when the width of the outer magnet of each unit magnet is defined as t1, the interval between the end parts of adjacent outer magnets is defined as d1, the moving distance of each unit magnet in the first direction is defined as SL, and the interval between the central parts of the bodies of adjacent central magnets is defined as W, the relationship of W = d1 + 3·t1 < SL is satisfied.

2. The sputtering device according to claim 1, wherein the central part of the body of the central magnet has a constant width, and the width of the end gradually becomes narrower toward the outside along the second direction.

3. The sputtering device according to claim 1, wherein the width of the inner space of the outer magnet surrounding the central magnet is narrower at the end in the second direction than at the central part of the body of the central magnet.

4. The sputtering device according to claim 3, wherein at the central part of the body of the central magnet, the inner space of the outer magnet has a constant width, and at the end, the width of the inner space gradually becomes narrower toward the outside along the second direction.

5. The sputtering device according to claim 4, wherein the width of the inner space of the outer magnet forms a step and gradually becomes narrower in stages at the end.

6. The sputtering device according to claim 4, wherein the width of the inner space of the outer magnet forms an inclination and continuously becomes narrower at the end.

7. The sputtering device according to claim 3, wherein the position where the width of the central magnet starts to become narrower coincides with the position where the width of the inner space of the outer magnet starts to become narrower along the second direction.

8. The sputtering device according to claim 3, wherein the position where the width of the central magnet starts to become narrower does not coincide with the position where the width of the inner space of the outer magnet starts to become narrower along the second direction.

9. The sputtering device according to claim 1, wherein when performing a vapor deposition operation, a plasma having a shape corresponding to the interval between the central magnet and the outer magnet is formed between the object and the target.

Images