TWI689608B - Sputtering target material and sputtering film-forming method using the same - Google Patents

Abstract

The present invention provides a sputtering target that can reduce the generation of particles caused by arc discharge or abnormal discharge. The sputtering target of the present invention is used for magnetron sputtering, and a plate-shaped member is detachably inserted into a non-ablation area located at the center of the target surface of the sputtering target. Preferably, when embedded in the sputtering target, the surface of the plate-like member on the target surface side is approximately the same height as the target surface before the sputtering target is ablated, or is disposed concavely from the target surface Down position.

Description

Sputtering target material and sputtering film-forming method using the same

The present invention relates to a magnetron sputtering target for forming a magnetic field on the surface of a target and performing sputtering, and a sputtering film-forming method using the target.

"Flat Panel Display (FPD), which is installed in mobile phones, portable electronic document machines, vending machines, car navigation, etc., is using a "touch panel" in which a finger or pen tip touches the display screen for input. universal. "Touch panel" is roughly divided into "resistive type" and "electrostatic capacitance type". The "resistive type" touch panel has the following structure: the X coordinate (or Y coordinate) formed on a transparent substrate containing a resin film ) The electrode pad for detection and the electrode pad for Y coordinate (or X coordinate) detection formed on the glass substrate are stacked such that the two electrode pads face each other with an insulator spacer interposed therebetween. Furthermore, according to the screen display, a pen or the like is used to press from the surface of the transparent substrate, whereby the two electrode pieces are electrically contacted, whereby the X coordinate and the Y coordinate of the pressed position can be detected.

On the other hand, the "electrostatic capacitance type touch panel" has the following structure: it includes an electrode sheet for detecting the X coordinate (or Y coordinate) opposite to the sandwiched insulating sheet, and the Y coordinate (or X coordinate) detection The laminated body of the electrode pad is equipped with an insulator such as glass. When the finger is brought close to the surface of the insulator according to the screen display, the capacitance of the X-coordinate detection electrode and the Y-coordinate detection electrode in the vicinity will change. Refers to the X and Y coordinates of the location. The above-mentioned "resistance type" and "electrostatic capacitance type" touch panels can recognize coordinates every time as long as the pen or the like is moved, and thus have a structure capable of inputting characters and the like.

As the conductive material constituting the electrode sheet, as described in Patent Document 1, a transparent conductive film such as indium tin oxide (ITO) has been widely used since then. This transparent conductive film has the advantage of being hard to be recognized by circuit patterns such as electrodes due to its excellent permeability in the visible wavelength region, but because its resistance value is higher than that of metal thin wires, it is not suitable for the enlargement of touch panels Or the shortcomings of increased response speed.

Therefore, as disclosed in Patent Document 2 or Patent Document 3, etc., with the recent increase in the size of touch panels, the use of nets suitable for the enlargement of touch panels or the increase in response speed due to low resistance values has begun to be used. Eye-shaped metal thin wire (metal film). However, metal thin wires (metal films) have a high reflectance in the visible wavelength region, so even if processed into a fine mesh structure, under high-brightness lighting, circuit patterns may be recognized, which may reduce the value of the product. Disadvantages.

In order to reduce the high reflectance of the thin metal wire (metal film) viewed from the transparent substrate side, to exhibit the characteristics of the thin metal wire (metal film) with low resistance value, as described in Patent Document 4 or Patent Document 5, There has been proposed a technique in which a reactive sputtering film-forming layer (also referred to as a blackened film) containing a metal oxide is interposed between a transparent substrate containing a resin film and a metal thin line (metal film).

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2003-151358

[Patent Document 2] Japanese Patent Laid-Open No. 2011-018194

[Patent Document 3] Japanese Patent Laid-Open No. 2013-069261

[Patent Document 4] Japanese Patent Laid-Open No. 2014-142462

[Patent Document 5] Japanese Patent Laid-Open No. 2013-225276

From the viewpoint of seeking a metal oxide film-forming efficiency, the reactive sputtering film-forming layer containing a metal oxide is usually used in a reactive gas environment containing oxygen by using a metal target (metal material) The film is continuously formed on the surface of the elongated resin film by reactive sputtering or the like. Furthermore, by sputtering using a metal target (metal material) such as copper or the like, a metal layer is continuously formed on the reactive sputtering film-forming layer, thereby performing a laminate for forming an electrode substrate film Film production.

However, if reactive sputtering using a reactive gas containing oxygen is carried out for a long time, the insulating film (oxide film) deposited in the non-ablated region on the target surface of the metal target becomes arcing The cause of this is that the particles generated by this arc discharge may adhere to the surface of the long resin film, which may cause a disconnection failure or a short circuit failure when forming circuit patterns such as electrodes. In addition, if the amount of the insulating film deposited in the non-ablation region increases, the insulating film is easily peeled off, and the peeled insulating film may enter the discharge space to cause abnormal discharge. If the particles generated by this abnormal discharge also adhere to the surface of the long resin film, it may cause a disconnection failure or a short-circuit failure when forming circuit patterns such as electrodes. The present invention is based on the previous question The purpose of the problem is to provide a sputtering target that can reduce the generation of particles caused by arc discharge or abnormal discharge.

The inventors found that by forming a groove in the non-ablated area located at the center of the target surface of the metal target, and periodically replacing the plate-shaped member that is freely fitted into the groove, the non-ablated area can be The accumulation amount of the insulating film of the metal is suppressed to a certain fixed amount or less, thereby suppressing the generation of arc discharge or abnormal discharge and reducing the amount of particles adhering to the surface of the long resin film, thus completing the present invention. That is, the sputtering target provided by the present invention is a sputtering target for magnetron sputtering, which is characterized in that a plate-shaped member is detachably inserted into the center of the target surface of the sputtering target In non-eroded areas.

In addition, the present invention provides a sputtering film forming method characterized in that a reactive sputtering film is formed using a sputtering cathode equipped with the sputtering target in an environment where a reactive gas is supplied.

According to the present invention, it is possible to easily remove the particle deposits generated by the reactive sputtering film formation in the non-ablation region attached to the center portion of the target surface of the sputtering target. With this, when a reactive sputtering film is formed on the surface of the resin film, it is possible to prevent the occurrence of defects caused by abnormal discharge due to the particle deposits, or the adhesion of particles.

10: Sputtering mesh coating machine

11: vacuum chamber

11a: spacer

12: Unwinding roller

13, 23: free roller

14, 22: Tension sensor roller

15: feed roller

16: can roller

17, 18, 19, 20: magnetron sputtering cathode

21: Rear feed roller

24: take-up roller

25, 26, 27, 28, 29, 30, 31, 32: gas discharge tube

40: Magnetron sputtering cathode

41: Frame

41a: Shell

41b: housing cover

42: Magnetic circuit

42a: magnet

42b: yoke

43: cooling plate

44: Cooling water

45: Sputtering target

45a: slot

46: Fixture

47: Ground shield

48: Insulation board

49: Plate-shaped member

50, 60, 70: resin film (transparent substrate)

51, 61, 71: Reactive sputtering film formation

52, 53, 62, 63, 72, 73: metal layer (copper layer)

64, 74: 2nd reactive sputtering film formation

A: Particle accumulation

F: Long resin film

FIG. 1 is a schematic front view of a film forming apparatus using a magnetron sputtering cathode provided with a sputtering target of the present invention.

2 is a longitudinal cross-sectional view of a magnetron sputtering cathode provided with a sputtering target of a specific example of the present invention.

3(a) and 3(b) are perspective views of a specific example of the sputtering target of the present invention.

4 is a schematic schematic cross-sectional view of a first laminate film that can be produced by using a film forming apparatus including a magnetron sputtering cathode of the sputtering target of the present invention.

FIG. 5 is a schematic schematic cross-sectional view of a modified example of the first laminate film that can be produced by using a film forming apparatus including a magnetron sputtering cathode of the sputtering target of the present invention.

6 is a schematic schematic cross-sectional view of a second laminate film that can be produced by using a film forming apparatus including a magnetron sputtering cathode of the sputtering target of the present invention.

7 is a schematic schematic cross-sectional view of an electrode substrate film obtained by patterning a second laminate film produced by a film forming apparatus using a magnetron sputtering cathode provided with a sputtering target of the present invention .

First, as a specific example of a film forming apparatus using a magnetron sputtering cathode provided with the sputtering target of the present invention, a sputter screen that can continuously form a film by a reactive sputtering method as shown in FIG. 1 The web coater 10 will be described. The sputtering mesh coater 10 shown in FIG. 1 can be suitably used in a case where the long resin film F conveyed by the roll-to-roll method in the vacuum chamber 11 continuously and efficiently A film forming process is performed on the surface.

If specifically described, various vacuum devices (not shown) such as dry pumps, turbo molecular pumps, cryogenic coils, etc. are incorporated in the vacuum chamber 11, and these vacuum devices are used to evacuate the vacuum chamber 11 during sputtering film formation. After depressurizing inside until the ultimate pressure is about 10 ^-4 Pa, the pressure can be adjusted to about 0.1 Pa ~ 10 Pa by introducing sputtering gas. A well-known gas such as argon gas is used as the sputtering gas, and a gas such as oxygen gas is further added according to the purpose. As long as the shape or material of the vacuum chamber 11 can withstand such a reduced pressure state, various shapes or materials can be used without particular limitation.

The vacuum chamber 11 is provided with a roll-out roll 12 and a take-up roll 24 for winding and winding up the long resin film F transported by roll-to-roll, and a roll-to-roll transport path is defined Various roller groups. Among the various roller groups, a can roll 16 positioned substantially at the center of the roller-to-roller conveyance path is driven by a motor and cooled by a refrigerant whose temperature is adjusted outside the vacuum chamber 11 By internal circulation, the long resin film F subjected to the film forming process requiring a heat load can be wound around the outer peripheral surface and cooled. Furthermore, the space where the can roller 16 is provided is separated from the space where the roller group other than the can roller 16 is provided by the partition plate 11 a.

In the roller group defining the conveyance path from the unwinding roller 12 to the can roller 16, a free roller 13 that guides the long resin film F is sequentially arranged, and tension sensing for measuring the tension of the long resin film F Feeder roller 14 and a motor-driven feed roller 15. The roller group which defines the conveyance path from the can roller 16 to the take-up roller 24 is similar to the above, and the motor-driven rear feed roller 21 which adjusts the circumferential speed with respect to the can roller 16 is sequentially arranged, The tension sensor roller 22 that measures the tension of the long resin film F, and the free roller 23 that guides the long resin film F.

By the rotation of the can roller 16 and the forward feed roller 15 and the rear feed roller 21 rotating in conjunction therewith, the long resin film F is taken out from the take-out roller 12 and taken up by the take-up roller 24. At this time, the tension balance of the long resin film F is maintained by torque control using the powder clutch of the take-out roller 12 and the take-up roller 24. In addition, the circumferential speeds of the forward feed roller 15 and the rear feed roller 21 can be adjusted with respect to the circumferential speed of the can roller 16 respectively, whereby the long resin film F can be closely adhered to the outer peripheral surface of the can roller 16.

At a position facing the outer periphery of the can roller 16, a long resin film is wound along the conveyance path defined on the outer periphery of the can roller 16 (that is, among the outer surfaces of the can roller 16) (F area), a magnetron sputtering cathode 17, a magnetron sputtering cathode 18, a magnetron sputtering cathode 19, and a magnetron sputtering cathode 20 are sequentially provided as a film forming means. The magnetron sputtering cathode 17 to the magnetron sputtering cathode 20 are respectively provided with a gas discharge pipe 25, a gas discharge pipe 26, and a gas discharge pipe for releasing reactive gas at the front part and the rear part of the long resin film F in the transport direction The tube 27, the gas discharge tube 28, the gas discharge tube 29, the gas discharge tube 30, the gas discharge tube 31, and the gas discharge tube 32.

Next, referring to the longitudinal sectional view of FIG. 2, the magnetron sputtering cathode 17, the magnetron sputtering cathode 18, the magnetron sputtering cathode 19 and the magnetron sputtering cathode 20 will be described in detail. The magnetron sputtering cathode 40 shown in FIG. 2 has a structure in which a magnetic circuit 42 is accommodated in a frame 41 including a substantially rectangular parallelepiped-shaped casing 41a and a rectangular casing cover 41b covering its opening. The magnetic circuit 42 includes a magnet 42a and a yoke 42b that supports the magnet 42a from the back side. In the case cover 41b, a cooling plate 43 is superposed on the surface opposite to the surface facing the magnetic circuit 42. In addition, in the housing cover 41b, A cooling water passage 44 through which a cooling medium such as cooling water passes is formed on the surface facing the cooling plate 43. In addition, between the housing 41a and the housing cover 41b, and between the housing cover 41b and the cooling plate 43 are sealed with a sealing material such as an O-ring.

In this cooling plate 43, a sputtering target 45 according to a specific example of the present invention is provided on the surface opposite to the surface facing the case cover 41b. The peripheral portion of the sputtering target 45 is provided with a step difference, and the sputtering target 45 is fixed to the cooling plate 43 by a jig 46 engaged with the step difference portion. In addition to the target surface of the sputtering target 45, a ground shield 47 is provided so that the sputtering target 45, the frame 41, the cooling plate 43, and the jig 46 are all enclosed, and the bottom of the housing 41a It is fixed to this ground shield 47 via an insulating plate 48. That is, the frame 41 that houses the magnetic circuit 42 and the sputtering target 45 are electrically insulated from the ground shield 47.

The magnetron sputtering cathode 40 of this structure has the target surface of the sputtering target 45 and the long resin film F as the film-forming object arranged in the vacuum chamber 11 as described above. When forming a film by sputtering, the inside of the vacuum chamber 11 is evacuated, and then Ar gas as a process gas is introduced. When a voltage is applied to the sputtering target 45 in this state, Ar gas is ionized by the electrons emitted from the sputtering target 45, and the ionized Ar gas collides with the target surface of the sputtering target 45 On the other hand, the target material is ejected, and the target material is deposited on the surface of the long resin film F as the film-forming object, thereby forming a thin film.

At this time, a polar magnetic field is generated on the target surface side of the sputtering target 45. In addition, a voltage of negative hundreds of volts is generally applied to the sputtering target 45, and on the other hand, the ground shield 47 at the periphery thereof is held As a ground potential, the potential difference generates a orthogonal electromagnetic field on the target surface side of the sputtering target 45. Two released from the target surface of the sputtering target 45 The secondary electrons move while drawing a cycloid orbit in a direction perpendicular to the orthogonal electromagnetic field on the target surface of the sputtering target 45. During this period, electrons that have collided with Ar gas and lost part of their energy undergo trochoid movement in the orthogonal electromagnetic field, and drift and move in the polar magnetic field.

In this period, the electrons collide with Ar gas again, as indicated by the ^{Ar + e - → Ar + +} 2e - as shown, by the action of α generate Ar ions and electrons. When the generated Ar ions diffuse into the sheath area, they rapidly accelerate toward the sputtering target 45 applied negatively. If Ar ions having a kinetic energy of several hundreds of eV collide with the sputtering target 45, the target surface of the sputtering target 45 emits sputtering particles by sputtering, and emits secondary electrons by γ action. By generating the above phenomenon in an avalanche shape, the plasma is maintained.

The electrons moving while depicting the trochoidal track by the magnetic circuit and electric field in the sputtering cathode 40 are concentrated on the portion where the magnetic force lines and the target surface of the sputtering target 45 become parallel, that is, the portions where the magnetic force lines and the electric field are orthogonal . Due to the concentration of electrons, collisions of electrons and Ar gas frequently occur, so the target material is concentrated due to ionized Ar gas. As a result, as shown in FIG. 2, erosion (erosion) occurs in the area of the sputtering target 45 except for the central portion and the outer peripheral portion of the target surface, and the central portion and the outer peripheral portion of the target surface become non-functional Eroded area.

In the case of the sputtering film formation, in addition to covering the long resin film F as the film-formed object, the target material that is shot also adheres to the non-ablated region of the sputtering target 45 to become Particle deposit A. In particular, reactive sputtering of sputtering film formation while supplying reactive gas such as oxygen or nitrogen in the sputtering film formation environment In this case, the particle deposit A becomes an oxide or nitride of a substance constituting the target material due to the reactive gas, and therefore is deposited in a state in which it is difficult to be corroded by Ar ions generated by plasma. The particle deposit A deposited in the above-mentioned manner is peeled off the sputtering target 45 in the sputtering film formation, and adheres to the long resin film F as the object to be film-formed, or causes arc discharge. In addition, if particles generated by arc discharge or abnormal discharge adhere to the long resin film F, a disconnection failure or a short-circuit failure may occur when forming circuit patterns such as electrodes.

Therefore, as shown in FIGS. 2 and 3(a) and 3(b), the sputtering target 45 according to a specific example of the present invention is provided with grooves in the non-ablation region located at the center of the target surface 45a, and the plate-shaped member 49 is detachably fitted into the groove 45a. Thereby, during magnetron sputtering, the particle deposit A attached to the non-ablation area of the sputtering target 45 can be easily removed by removing the plate-shaped member 49.

That is, it is replaced with a new plate-shaped member 49 before the arc discharge caused by the insulating film deposited on the non-ablated portion or the abnormal discharge caused by peeling frequently occurs, whereby the adhesion to the long resin film F can be suppressed The amount of particles increases. In this way, if the sputtering target of the present invention is used, no particles or the like adhere to the surface of the long resin film as the film-forming surface, so that a homogeneous sputtering film containing no foreign matter or the like can be formed. Furthermore, it is difficult to remove only the particle deposits in the non-ablated part of the central portion of the sputtering target without using the plate-like member of the present invention, and if it is to be forcibly removed, there is contamination when removing the particle deposits The risk of sputtering targets.

As described above, the non-ablation region also exists on the outer peripheral portion of the sputtering target, so it can also be considered that the outer peripheral portion is provided with the same plate-shaped member as the central portion. Functional building blocks. However, if it is the outer peripheral portion of the sputtering target, by using, for example, a rectangular frame-shaped covering member, it can be easily covered without hindering sputtering, thereby obtaining a plate with the non-ablated area provided in the central portion The same function as the shape member. The covering member is preferably detachably provided on the jig 46 or the like by a coupling means such as a screw. Thereby, it is only necessary to provide the plate-shaped member only in the central portion of the sputtering target, so the processing cost of the sputtering target can be suppressed. In addition, it has been confirmed that even if the covering member is not provided on the outer peripheral portion of the sputtering target, but the plate-like member is provided only on the central portion, defects such as particles of the sputtered film are significantly reduced.

When embedded in the groove 45a of the sputtering target 45, the surface of the plate-like member 49 on the target surface side is preferably the target surface before the sputtering target 45 is eroded (indicated by the chain line in FIG. 2 ) Is approximately the same height, or is located at a position where the target surface is recessed from before the ablation. In other words, the surface of the plate-shaped member 49 on the target surface side preferably does not protrude from the flat target surface before the sputtering target 45 is ablated and becomes convex. If the plate-shaped member 49 protrudes into a convex shape from the target surface before the sputtering target 45 is ablated, the state of the electric field may change and abnormal discharge such as arc discharge may occur, or the sputtering of the plate-shaped member 49 may be promoted. The composition of the film formed on the long resin film F deviates from the desired composition and is not ideal.

The plate-shaped member 49 is desirably made of the same material as the sputtering target 45. When the material of the sputtering target 45 is an alloy, the plate-shaped member 49 may be constituted by a part of metal constituting the alloy of the sputtering target 45. By setting the material of the plate-like member 49 to the same material as the sputtering target 45 as described above, or when the sputtering target 45 is an alloy, the same metal as the metal constituting part of these metals is used, even Have When the plate-shaped member 49 is sputtered, the film formed on the surface of the long resin film F can also be prevented from being contaminated by the plate-shaped member 49 during the film formation process. In addition, the plate-shaped member 49 can be attached to a sputtering target by well-known attachment means, such as a screw.

The surface of the plate-like member 49 on the target material surface side preferably has a surface roughness of 10 μm or more and 500 μm or less in terms of ten-point average roughness Rz, and Rz is more preferably 20 μm to 100 μm. If the surface roughness Rz of the plate-like member 49 is less than 10 μm, the anchoring effect is reduced, and the particle deposits are easily separated. On the other hand, if the surface roughness Rz exceeds 500 μm, an abnormal discharge easily occurs at the vertex of the rough surface of the surface of the plate-like member 49 due to the voltage applied to the sputtering cathode. For example, although it also depends on the structure of the sputtering cathode or the structure of the sputtering apparatus, when the surface roughness Rz of the plate-like member 49 is 750 μm, if 500 V is applied to the sputtering cathode, abnormal discharge may sometimes occur. Furthermore, the surface roughness of the plate-like member 49 can be adjusted by sandblasting or spraying.

Next, a laminate film obtained by performing reactive sputtering on the film forming apparatus using the sputtering target material according to a specific example of the present invention, and obtained by patterning the laminate film The electrode substrate film will be described. The film forming apparatus provided with the sputtering target of a specific example of the present invention can be manufactured on at least one surface of a transparent substrate including a resin film as described later, and the first layer is stacked from the side of the transparent substrate The first layered film of the reactive sputtering film-forming layer and the second metal layer, or it can be produced on at least one surface of a transparent substrate including a resin film, and the first layer is deposited from the side of the transparent substrate The second laminate film of the reactive sputtering film-forming layer, the second metal layer, and the third reactive sputtering film-forming layer.

First, the first laminate film will be described, for example, as shown in FIG. 4, the first laminate film includes a transparent substrate 50 including a resin film, and is formed by a dry film formation method (dry plating method) A reactive sputtering film-forming layer 51 formed on both surfaces of the transparent substrate 50, and a metal layer formed on the reactive sputtering film-forming layer 51 by a dry film forming method (dry plating method) 52. Moreover, the film forming apparatus provided with the sputtering target of a specific example of the present invention can be suitably used for forming the reactive sputtering film-forming layer 51. The film formation of the metal layer 52 may be formed only by the dry film formation method (dry plating method) as shown in FIG. 4 or the dry film formation method (dry plating) as shown in FIG. 5 The coating method) is formed in combination with the wet film forming method (wet plating method).

That is, the laminate film shown in FIG. 5 includes a transparent substrate 50 including a resin film, and a film thickness formed on both surfaces of the transparent substrate 50 by a dry film formation method (dry plating method) is 15 nm. ~30 nm reactive sputtering film-forming layer 51, a metal layer 52 formed on the reactive sputtering film-forming layer 51 by dry film forming method (dry plating method), and wet film forming Method (wet plating method) to form a metal layer 53 on the metal layer 52.

Next, the second laminate film will be described with reference to FIG. 6. The second laminate film of FIG. 6 is formed on the metal layer of the first laminate film shown in FIG. 5 by further forming a second reactive sputtering film-forming layer. Specifically, it includes: a transparent substrate 60 including a resin film, and a reactive sputtering method in which a film thickness of 15 nm to 30 nm is formed on both surfaces of the transparent substrate 60 by a dry film formation method (dry plating method) The film layer 61, the metal layer 62 formed on the reactive sputtering film-forming layer 61 by a dry film-forming method (dry plating method), and the wet film-forming method (wet plating method) in A metal layer 63 formed on the metal layer 62 and a second reactive sputtering film formed on the metal layer 63 by a dry film formation method (dry plating method) with a film thickness of 15 nm to 30 nm Layer 64.

In the second laminate film shown in FIG. 6, a reactive sputtering film layer 61 and a second reactive sputtering film are formed on both surfaces of the metal layer including the metal layer 62 and the metal layer 63 as a whole膜层64。 64 layer. The reason for this is that, when the electrode substrate film produced using the laminate film is incorporated into a touch panel, the circuit pattern of the mesh structure including the metal fine layered wires can be reflected and not seen. Furthermore, when using the first laminate film obtained by forming a reactive sputtering film-forming layer on one surface of a transparent substrate containing a resin film and forming a metal layer on the reactive sputtering film-forming layer In the case of an electrode substrate film, the circuit pattern from the transparent substrate can also be prevented from being recognized.

The reason for performing reactive sputtering as described above is that when an oxide target is used for forming a reactive sputtering film-forming layer containing a metal oxide, the film forming speed becomes slow and it is not suitable for mass production. Therefore, a reactive film forming method such as reactive sputtering, which uses a Ni-based metal target (metal material) capable of high-speed film formation and controls the reactive gas containing oxygen while introducing it, is used. In addition, as a method of controlling the reactive gas, the following four methods are known: (1) a method of releasing a fixed flow of reactive gas, (2) a method of releasing a reactive gas while maintaining a fixed pressure, ( 3) Method of releasing reactive gas in such a way that the impedance of the sputtering cathode becomes fixed (impedance control), and (4) Method of releasing reactive gas in such a way that the strength of the sputtered plasma becomes fixed (plasma emission control) .

When the reaction by introducing reactive gas into the film forming device as described When the reactive sputtering method is used to form the reactive sputtering layer, the reactive gas that becomes the sputtering environment can be obtained by introducing oxygen into argon gas. By introducing oxygen as described above, a NiO film (not completely oxidized) or the like can be formed by reactive sputtering using a Ni-based metal target (metal material) or the like. The oxygen content of the reactive gas depends on the type of the film forming apparatus or the metal target (metal material), as long as the optical characteristics such as the reflectance in the reactive sputtering film-forming layer or the etchability generated by the etching solution are appropriately set That is, it is usually ideal to be 15% by volume or less.

The reactive sputtering film-forming layer is formed by using a Ni-based alloy containing Ni monomer or adding one or more elements selected from Ti, Al, V, W, Ta, Si, Cr, Ag, Mo, and Cu The metal material and the reactive gas containing oxygen are formed by the reaction film forming method. Furthermore, the Ni-based alloy is preferably a Ni-Cu alloy. In addition, if the oxidation of the metal oxide constituting the reactive sputtering film-forming layer is excessively progressed, the reactive sputtering film-forming layer becomes transparent, so it is necessary to set the oxidation level to such an extent that it becomes a blackened film.

Furthermore, in the reaction film forming method, in addition to the magnetron sputtering using the sputtering target of the present invention, ion beam sputtering, vacuum evaporation, ion plating, chemical vapor deposition (Chemical Vapor Deposition, CVD), etc. In addition, the optical constant (refractive index, extinction coefficient) at each wavelength of the reactive sputtering film-forming layer is greatly affected by the degree of reaction, that is, the degree of oxidation, and is not determined solely by the metal material containing the Ni-based alloy.

The constituent material (metal material) of the metal layer is not particularly limited as long as it is a metal having a low resistance value, and examples thereof include Cu monomers, and optional additions. Cu-based alloy from one or more elements of Ti, Al, V, W, Ta, Si, Cr, Ag, or Ag alone, or added with selected from Ti, Al, V, W, Ta, Si, Cr In particular, the Ag-based alloy of one or more elements in Cu is preferably Cu alone, particularly from the viewpoint of the workability of the circuit pattern or the resistance value. In addition, the film thickness of the metal layer depends on the electrical characteristics and is not determined by the optical element, but it is usually set to a film thickness that cannot measure the level of transmitted light.

The material of the resin film applied to the laminate film is not particularly limited, and specific examples thereof include: selected from polyethylene terephthalate (Polyethylene terephthalate, PET) and polyether sulfone (Polyethersulfone, PES), Polyarylate (PAR), Polycarbonate (PC), Polyolefin (Po), Polyacetylene (PO), Triacetyl Cellulose (TAC) and norbornene resin resin materials A monomer of the film, or a composite of a resin film monomer selected from the resin materials and an acrylic organic film covering one or both sides of the monomer. In particular, the norbornene resin material can be exemplified by Zeonor (trade name) of Zeon Corporation or Arton (trade name) of JSR Corporation. Wait. In addition, since the electrode substrate film produced using the laminate film of the present invention is used for a “touch panel” or the like, among the resin films, those having excellent transparency in the visible wavelength range are preferably used.

The first laminate film or the second laminate film as described above is patterned, and the wiring is processed into, for example, a thin laminated line having a line width of 20 μm or less, whereby an electrode substrate film can be produced. For example, a method of obtaining a sensor panel made of a metallic mesh from the second laminate film will be described. Furthermore, in the following description, the The sensor panel made of metal mesh is called an electrode substrate film. Specifically, the laminate film of the laminate film shown in FIG. 6 is etched to obtain the electrode substrate film shown in FIG. 7.

The electrode substrate film shown in FIG. 7 has a transparent substrate 70 including a resin film, and a circuit pattern of a mesh structure including metal build-up thin wires provided on both sides of the transparent substrate 70, the metal build-up thin wires Has a line width of 20 μm or less and includes the reactive sputtering film layer 71 of the first layer, the metal layer 72 of the second layer, the metal layer 73, and the second reactivity of the third layer from the transparent substrate 70 side Sputtering into a film layer 74.

When the laminate film wiring is processed into an electrode substrate film, it can be processed by a known subtractive method. The subtractive method is to form a photoresist film on the surface of the layered film of the layered body film, and expose and develop the photoresist film remaining in the portion where the wiring pattern is to be formed, and then remove the layered layer by chemical etching A laminated film in a portion where there is no photoresist film on the film surface. As an etchant for chemical etching, an aqueous solution of ferric chloride or an aqueous solution of copper chloride can be used.

From the standpoint of the manufacturing process of such an electrode substrate film, the laminate film (reactive sputtering film-forming layer and metal layer) constituting the laminate film preferably has easy etching by an aqueous solution of copper chloride or an aqueous solution of ferric chloride, etc. Characteristics of etching. In addition, the circuit pattern of the etched electrode and the like preferably has characteristics that are difficult to be recognized under high-brightness illumination.

The electrode (wiring) pattern of the electrode substrate film formed in the above-described manner can be made into a stripe shape or a lattice shape for a touch panel, whereby the electrode substrate film of the present invention can be used Used for touch panel. In this case, the metal thin-layer build-up wires whose wiring is processed into electrode (wiring) patterns maintain the build-up structure of the laminate film, so it is extremely difficult to use as a circuit pattern for electrodes or the like provided on a transparent substrate even under high-brightness illumination Provided by the electrode substrate film recognized.

[Example]

Hereinafter, the examples of the present invention will be specifically described by listing comparative examples, but the present invention is not limited by the following examples.

[Example]

The film forming apparatus (sputter mesh coater) shown in FIG. 1 was used to produce a laminate film as shown in FIG. 4. For the can roller 16, a stainless steel roller having a diameter of 600 mm and a width of 750 mm was used, and the outer peripheral surface was hard chrome plated. For the forward feed roller 15 and the rear feed roller 21, a stainless steel roller with a diameter of 150 mm and a width of 750 mm was used, and the outer peripheral surface was hard chrome plated.

A gas discharge tube 25, a gas discharge tube 26, and a gas discharge tube 27 are provided on the upstream and downstream sides of the magnetron sputtering cathode 17, the magnetron sputtering cathode 18, the magnetron sputtering cathode 19, and the magnetron sputtering cathode 20 , The gas discharge pipe 28, the gas discharge pipe 29, the gas discharge pipe 30, the gas discharge pipe 31, the gas discharge pipe 32. For the magnetron sputtering cathode 17 and the magnetron sputtering cathode 18, a Ni-Cu target for reactive sputtering film formation is used. As shown in FIGS. 3(a) and 3(b), a groove extending in the longitudinal direction of the cathode is formed in the non-ablated region at the center of the target surface of the Ni-Cu target, and A plate-shaped member made of Cu that was subjected to a spraying treatment so that the surface roughness of the surface on the target surface side was 50 μm in ten-point average roughness Rz was inserted into the groove in. In addition, the surface of the plate-shaped member on the target surface side and the target surface of the Ni-Cu target are set to the same height. On the other hand, a Cu target for a general metal layer is mounted on the magnetron sputtering cathode 19 and the magnetron sputtering cathode 20.

A PET film with a width of 600 mm and a length of 1200 m was used for the long resin film F constituting the transparent substrate, and the can roller 16 was cooled and controlled to 0°C. In this state, after evacuating the vacuum chamber 11 with a plurality of dry pumps to 5 Pa, a plurality of turbo molecular pumps and cryogenic coils are used to evacuate to 1×10 ^-4 Pa. Then, while conveying the long resin film F at a conveying speed of 2 m/min, while introducing argon gas from the gas discharge pipe 29, the gas discharge pipe 30, the gas discharge pipe 31, the gas discharge pipe 32 at 300 sccm, the cathode 19 and the cathode 20 In order to obtain a Cu film thickness of 80 nm, the film is formed by power control.

On the other hand, in order to form a reactive sputtering film-forming layer, a mixed gas mixed with 280 sccm of argon gas and 15 sccm of oxygen gas is introduced from the gas discharge tube 25, the gas discharge tube 26, the gas discharge tube 27, and the gas discharge tube 28. With the cathode 18, the film formation is performed by controlling the power with an applied voltage of about 500 V to obtain a 30-nm Ni-Cu oxide film thickness. In addition, while replacing the plate-like member in the center portion with a new product every 3 batches, a total of 12 batches of laminate films were produced. As a result of confirming the adhesion of particles of 10 μm or more to the obtained laminate film by an image inspection device using image analysis of a computer, an average of 53 particles per batch was confirmed.

[Example 2]

A total of 12 batches of products were produced in the same manner as in Example 1, except that the surface roughness of the plate-shaped member made of Cu was 10 μm in terms of ten-point average roughness Rz. Layer body membrane. The adhesion of particles of 10 μm or more in the obtained laminate film was confirmed in the same manner as in Example 1. As a result, an average of 61 particles per batch was confirmed.

[Example 3]

A total of 12 batches of laminate films were produced in the same manner as in Example 1, except that the surface roughness of the plate-shaped member made of Cu was 20 μm in terms of ten-point average roughness Rz. As a result of confirming the adhesion of particles of 10 μm or more in the obtained laminate film in the same manner as in Example 1, an average of 55 particles per batch was confirmed.

[Example 4]

A total of 12 batches of laminate films were produced in the same manner as in Example 1, except that the surface roughness of the plate-shaped member made of Cu was 200 μm in terms of ten-point average roughness Rz. The adhesion of particles of 10 μm or more in the obtained laminate film was confirmed in the same manner as in Example 1. As a result, an average of 58 particles per batch was confirmed.

[Example 5]

A total of 12 batches of laminate films were produced in the same manner as in Example 1, except that the surface roughness of the plate-shaped member made of Cu was 450 μm in terms of ten-point average roughness Rz. The adhesion of particles of 10 μm or more in the obtained laminate film was confirmed in the same manner as in Example 1. As a result, an average of 58 particles per batch was confirmed.

[Example 6]

A total of 12 batches of laminate films were produced in the same manner as in Example 1, except that the surface roughness of the plate-shaped member made of Cu was 5 μm in terms of ten-point average roughness Rz. As a result of confirming the adhesion of particles of 10 μm or more in the obtained laminate film in the same manner as in Example 1, an average of 130 particles per batch was confirmed.

[Comparative Example 1]

A total of 12 batches of laminate films were produced in the same manner as in Example 1, except that the previous target was used for the Ni-Cu target for reactive sputtering film formation. The adhesion of particles of 10 μm or more in the obtained laminate film was confirmed in the same manner as in Example 1. As a result, an average of 370 particles per batch were confirmed.

In a batch of 1200 m laminate film, it is desirable that the number of particles of 10 μm or more is small. Specifically, if it is 150 particles/batch or less, it is difficult to cause practical problems, but more preferably 100 particles/batch Below the batch. As described above, in Examples 1 to 6 using the sputtering target of the present invention, the number of particles of 10 μm or more can be suppressed to 150 particles/batch or less. On the other hand, in Comparative Example 1 using the previous sputtering target, the number of particles of 10 μm or more was twice or more than 150/batch.

45‧‧‧Sputtering target

45a‧‧‧slot

49‧‧‧Plate member

Claims (6)

A sputtering target used for magnetron sputtering, characterized in that a plate-shaped member is detachably inserted into a bottom of a non-ablated area provided in a central portion of a target surface of the sputtering target Inside the slot. The sputtering target according to item 1 of the scope of the patent application, wherein, when embedded in the sputtering target, the surface on the target surface side of the plate-like member and the sputtering target before ablation The target surface of is approximately the same height, or is arranged at a position recessed from the target surface. The sputtering target according to item 1 or 2 of the patent application range, wherein the surface roughness of the plate-like member on the target surface side is 10 μm or more and 500 μm or less in terms of ten-point average roughness Rz. The sputtering target according to item 3 of the patent application range, wherein the surface of the plate-like member on the target surface side is roughened by sandblasting or spraying. A method for forming a sputtering film, characterized in that: in an environment where a reactive gas is supplied, a sputtering cathode equipped with a sputtering target as described in any one of claims 1 to 4 is used for reaction Sexual sputtering to form a film. The sputtering film-forming method as described in item 5 of the patent application range, wherein the reactive gas is any one of oxygen, nitrogen, and steam.

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