KR102274149B1 - Sputtering target member, method for producing sputtering target member, sputtering target, sputtered film, method for producing sputtered film, film body, laminate structure, and organic el device - Google Patents

Abstract

A sputtering target member suitable for obtaining a sputtering film having characteristics such as a high work function and a refractive index of 1.9 to 2.1 at a wavelength of 633 nm is provided. It is a sputtering target member formed of Ga, In, O, and an unavoidable impurity, and the atomic ratio of Ga/In is 0.90 or more and 1.11 or less, and the surface analysis in EPMA WHEREIN: (Ga, In) ₂ O _{3 with respect to the whole crystal phase} The area ratio of the phase is 90% or more.

Description

A sputtering target member, the manufacturing method of a sputtering target member, a sputtering target, a sputtering film, the manufacturing method of a sputtering film, a film body, a laminated structure, and organic electroluminescent apparatus TECHNICAL FIELD TECHNICAL FIELD FOR PRODUCING SPUTTERED FILM, FILM BODY, LAMINATE STRUCTURE, AND ORGANIC EL DEVICE}

TECHNICAL FIELD The present invention relates to a sputtering target member, a method for manufacturing a sputtering target member, a sputtering target, a sputtering film, a method for manufacturing a sputtering film, a film body, a laminated structure, and an organic EL device.

An organic electroluminescent (EL) device is provided with the organic layer clamped between a pair of electrodes called an upper electrode (cathode) and a lower electrode (anode). As an organic layer, it is well known that it contains an organic hole transport layer and an organic light emitting layer. Holes injected from the lower electrode and electrons injected from the upper electrode recombine in the organic light emitting layer to create an excited state and emit light when returning to the ground state. . In order to efficiently inject holes and electrons into the organic hole transport layer and the organic light emitting layer, a metal having a low work function is typically used for the upper electrode, and a sputtering film made of a metal complex oxide having a high work function for the lower electrode is used. .

Here, when manufacturing the sputtering film serving as the lower electrode, the high work function film is formed on a substrate for film formation such as glass or plastic or on a metal film formed on it, a sputtering target member formed by an oxide sintered body is used for sputtering. is encapsulated by Therefore, in order to obtain a sputtering film which has a high work function, attention is paid to the sputtering target member which is a raw material.

For example, Patent Document 1 mainly consists of Ga, In, and O, and contains 49.1 atomic% or more and 65 atomic% or less of Ga with respect to all metal atoms, and mainly contains a GaInO ₃ phase having a _{β-Ga 2} O _{3 type structure. and an In 2} O ₃ phase of a bixbite-type structure, _{and an X-ray diffraction peak intensity ratio defined by In 2} O ₃ phase (400)/β-GaInO ₃ phase (111) × 100 (%) is 45% or less, and , a sintered target for producing a transparent conductive film having a density of 5.8 g/cm 3 or more is described. It is described that the transparent conductive film obtained by the sputtering method using such a sintered compact target shows a work function of 5.1 eV or more, and shows a refractive index of 1.65 or more and 1.85 or less in wavelength 633 nm.

Japanese Patent Laid-Open No. 2007-224386

In recent years, development of organic EL has progressed, and various structures have been proposed by manufacturers of respective electronic devices. Under such circumstances, in an electronic device, since it is important to optimize an optical characteristic, it is preferable to propose the sputtering target member which can provide the sputtering film which has the refractive index according to the structure of each electronic device. Therefore, in order to obtain the sputtering film different from the refractive index of patent document 1, in the sputtering target member which is a well-known technique, it is thought that there is still room for improvement.

Then, embodiment of this invention has a high work function, and the refractive index aims at providing the sputtering target member suitable for obtaining the sputtering film whose refractive index is 1.9-2.1 in wavelength 633nm.

That is, in one aspect of the present invention, it is a sputtering target member formed of Ga, In, O, and unavoidable impurities, the atomic ratio of Ga/In is 0.90 or more and 1.11 or less, and in the surface analysis in EPMA, the entire crystalline phase (Ga, in) ₂ O ₃ on the area ratio is not less than about 90%, and a sputtering target member.

In one Embodiment of the sputtering target member which concerns on this invention, the atomic ratio of the said Ga/In is 0.95 or more and 1.05 or less.

In one Embodiment of the sputtering target member which concerns on this invention, the said area ratio is 95 % or more.

In one Embodiment of the sputtering target member which concerns on this invention, a relative density is 94 % or more.

In one Embodiment of the sputtering target member which concerns on this invention, a volume resistivity is 1.0x10 ³ ohm*cm or less.

In one embodiment of the sputtering target member according to the present invention, when a sputtering film is formed by changing the amount of oxygen in the sputtering gas from 0 to 3% by volume, the work function of the sputtering film is in the range of 5.0 to 6.0 eV.

In one Embodiment of the sputtering target member which concerns on this invention, it is cylindrical shape or flat plate shape.

Moreover, this invention is another one side. WHEREIN: It is a sputtering target provided with the said any sputtering target member and a base material.

In addition, in another aspect, the present invention is a method for producing any of the sputtering target members described above, _{mixing In 2} O ₃ powder and Ga ₂ O ₃ powder so that the atomic ratio of Ga/In is 0.90 or more and 1.11 or less to obtain a mixed powder It is the manufacturing method of the sputtering target member including the mixing process obtained and the sintering process which sinters the said mixed powder at sintering temperature above 1400 degreeC and less than 1600 degreeC, and obtaining a sintered compact.

In one Embodiment of the manufacturing method of the sputtering target member which concerns on this invention, the said sintering temperature is 1450 degreeC - 1550 degreeC.

In one Embodiment of the manufacturing method of the sputtering target member which concerns on this invention, the said sintering process WHEREIN: Sintering holding time is 5 to 20 hours.

Further, in another aspect, the present invention is formed of Ga, In, O and unavoidable impurities, the atomic ratio of Ga/In is 0.85 or more and 1.15 or less, and the refractive index at a wavelength of 633 nm is 1.9 to 2.1, It is a sputtering film having a work function of 5.0 to 6.0 eV.

In one embodiment of the sputtering film according to the present invention, the volume resistivity is 1.0 Ω·cm or less.

In one embodiment of the sputtering film according to the present invention, the extinction coefficient at a wavelength of 633 nm is 0.01 or less.

In one embodiment of the sputtering film according to the present invention, it is amorphous.

Moreover, this invention is another one side. WHEREIN: It is a manufacturing method of a sputtering film including the film-forming process of forming a sputtering film into a film using any said sputtering target member.

In one embodiment of the method for manufacturing a sputtering film according to the present invention, a step of annealing the sputtering film at 200°C or lower is included after the film-forming step.

In one embodiment of the method for manufacturing a sputtering film according to the present invention, in the film forming step, the sputtering film is formed while annealing at 200°C or lower.

In one Embodiment of the manufacturing method of the sputtering film which concerns on this invention, in the said film-forming process, the oxygen amount in sputtering gas is implemented to 10 volume% or less.

Moreover, this invention is another one side. WHEREIN: It is a film body provided with the said any sputtering film|membrane.

In one embodiment of the film body according to the present invention, the first metal film in contact with the first main surface of the sputtering film is further provided.

In one embodiment of the film body according to the present invention, an oxide barrier film in contact with the main surface of the first metal film is further provided.

In one embodiment of the film body according to the present invention, an oxide conductive film in contact with the first main surface of the sputtering film is provided.

In one embodiment of the film body according to the present invention, a first metal film in contact with the main surface of the oxide conductive film is further provided.

In one embodiment of the film body according to the present invention, an oxide barrier film in contact with the main surface of the first metal film is further provided.

In one embodiment of the film body according to the present invention, the oxide conductive film has a volume resistivity of 1.0 × 10 ^-3 Ω·cm or less.

In one Embodiment of the film body which concerns on this invention, the said oxide conductive film is formed with at least 1 sort(s) chosen from the group of ITO, IZO, and AZO.

In one Embodiment of the film body which concerns on this invention, the said 1st metal film contains 90 mass % or more of 1 type(s) or 2 or more types selected from the group of Ag, Cu, Ni, Fe, Cr, Al, and Co. is formed with

Moreover, this invention is another one side. WHEREIN: It is a laminated structure provided with the said any film body, and the glass substrate or resin substrate which contact|connected the outermost main surface of the said film body in the 1st main surface side of the said sputtering film.

In one Embodiment of the laminated structure which concerns on this invention, the organic layer which contact|connects the 2nd main surface opposite to the 1st main surface of the said sputtering film is further provided.

In one embodiment of the laminated structure according to the present invention, a second metal film in contact with the main surface of the organic layer is further provided.

In one embodiment of the laminated structure according to the present invention, the second metal film is formed of one or more selected from the group consisting of Al, In, W, Ti, Mo, Mg-Ag and Ag-Al. .

In another aspect, the present invention is an organic EL device in which a sealing layer, any of the above laminated structures, a thin film transistor, and a substrate are laminated in this order.

The sputtering target member which concerns on one Embodiment of this invention is suitable for obtaining the sputtering film which has the characteristic of a high work function and refractive index of 1.9-2.1.

BRIEF DESCRIPTION OF THE DRAWINGS It is a flowchart for demonstrating one Embodiment of the manufacturing method of the sputtering target member which concerns on this invention.
It is sectional drawing for demonstrating one Embodiment of the laminated structure which concerns on this invention.
It is sectional drawing for demonstrating other embodiment of the laminated structure which concerns on this invention.
It is sectional drawing for demonstrating other embodiment of the laminated structure which concerns on this invention.
It is sectional drawing for demonstrating other embodiment of the laminated structure which concerns on this invention.
It is sectional drawing for demonstrating other embodiment of the laminated structure which concerns on this invention.
It is sectional drawing for demonstrating other embodiment of the laminated structure which concerns on this invention.
Fig. 8(A) is a diagram showing an SE image (500 times) of the target cross section of the sputtering target member obtained in Example 1, (B) is the X-ray diffraction (XRD) of the sputtering target member obtained in Example 1 It is a graph showing the analysis result.

Hereinafter, this invention is not limited to each embodiment, The component can be changed and embodied in the range which does not deviate from the summary. In addition, various inventions can be formed by appropriate combination of a plurality of constituent elements disclosed in each embodiment. For example, some components may be deleted from all the components described in the embodiment. In addition, you may combine the components of different embodiment suitably.

[One. sputtering target member]

In one Embodiment, the sputtering target member which concerns on this invention is a sputtering target member formed from Ga, In, O, and an unavoidable impurity, Ga/In atomic ratio is 0.90 or more and 1.11 or less, Surface analysis in EPMA analysis In , the area ratio of the (Ga, In) ₂ O ₃ phase is 90% or more.

Hereinafter, an example of the conditions in which the said sputtering target member is suitable is demonstrated.

(Furtherance)

In one Embodiment of the sputtering target member which concerns on this invention, Ga, In, O, and remainder are formed from an unavoidable impurity. As an unavoidable impurity, in a metal or metal oxide product, when it exists in a raw material or mixes unavoidably in a manufacturing process, for example, the medium etc. at the time of raw material powder grinding|pulverization are mentioned. Although originally unnecessary, it is a permissible impurity because it is in trace amounts and does not affect the properties of metals or metal oxide products. The sputtering target member which concerns on this invention WHEREIN: Sn is contained as an unavoidable impurity, for example, The total amount is generally 1000 mass ppm or less, Typically 500 mass ppm or less, More typically, 100 mass less than ppm.

The atomic ratio of Ga/In is 0.90 or more and 1.11 or less. _{From the viewpoint of increasing the ratio of the (Ga, In) 2} O ₃ phase, the Ga/In atomic ratio is 0.90 or more on the lower limit side, preferably 0.95 or more, and more preferably 0.97 or more. Similarly, the upper limit of the atomic ratio of Ga/In is 1.11 or less, preferably 1.05 or less, and more preferably 1.03 or less.

In one Embodiment of the sputtering target member which concerns on this invention, Ga and In may exist in the form of an oxide. In one embodiment of the sputtering target member according to the present invention, a peak identified as _{(Ga, In) 2} O ₃ is observed from the viewpoint of adjusting the refractive index of the sputtering film to a target value in X-ray diffraction. . Here, in the ICDD (International Center for Diffraction Data) card, (Ga, In) ₂ O ₃ is No. 00-014-0564.

XRD measurement is performed in the following procedure. The sputtering target member to be measured is cut in the thickness direction, and the measurement surface (target cross-section side) is polished with abrasive paper having an average particle diameter #400 of abrasive grains conforming to JIS R 6010: 2000 as a measurement sample, X-ray diffraction Using the method, an X-ray diffraction chart is obtained under the following measurement conditions. In addition, the analysis software used PDXL. PDXL has a function of automatically calculating a shift of a peak due to employment or the like in software, shifting the peak of the ICDD card, and making it easier to identify.

<Measurement conditions>

An example of an XRD diffractometer: Smart Lab (manufactured by Rigaku Co., Ltd.)

Tube voltage: 40kV

Tube current: 30mA

Measurement range: 2θ = 10° to 90°

Scan axis: 2θ/θ

Scan speed: 10°/min

Step Width: 0.01°

Analysis software: PDXL (supplied with Smart Lab)

In the surface analysis in the EPMA analysis, _{the area ratio of the (Ga, In) 2} O ₃ phase is measured on the cross-sectional side of the target. It is preferable that the area ratio of the _{(Ga, In) 2} O ₃ phase is 90% or more from the viewpoint of obtaining a sputtering film having a high work function and having a refractive index of 1.9 to 2.1. This judgment is made from comparison with XRD. It is preferable that the area ratio of (Ga, In) ₂ O ₃ phase is 90 % or more, and it is more preferable that it is 95 % or more. However, the upper limit is typically 100% or less, and more typically 99% or less.

In addition, the surface analysis by EPMA is demonstrated below.

A sputtering target member is cut out and it is set as a test piece. Next, what cut this test piece to about 1 cm x 1 cm x 1 cm square with a slicing machine is set as a measurement sample, and mirror polishing is performed using an abrasive. The polished surface of the test piece is measured by surface analysis using an electron beam microanalyzer (eg, JXA-8500F, manufactured by Nippon Electronics Co., Ltd.), and at least three arbitrarily selected points are measured.

<Measurement conditions>

Pressurized current: 15.0kv

Irradiation current: 1.0-2.0×10 ^-7 A

Measurement magnification: 500 times

Resolution: 256×256dpi

Scan: Beam Scan

In addition, when calculating|requiring the area ratio of (Ga, In) ₂ O ₃ phase, it carries out with the following procedure.

1. Display the result of face analysis.

2. Particle measurement is performed on the surface analysis results of metal elements to determine the area where Ga and In overlap. This area, (Ga, In) ₂ O ₃ is not substantially check only existence of, that the coexistence Ga and In confirmed by EPMA, (Ga, In) by XRD by the art sputtering target member above ₂ O ₃ It is to be saved by determining that it is an award.

Particle measurement is made under the following conditions. In the case of using the particle measurement of the software included with the JXA-8500F, it is necessary to select a filter, a binarization method, a labeling method, etc., each of which is as follows.

<Conditions for particle measurement>

Filter: Smoothing Filter

Binarization: Automatic

Labeling of binarization 8 Linked, outer peripheral particles are also labeled.

Measurement area occupied by labeling

In terms of the occupied area ratio, the area ratio of the region containing In and Ga of each of the labeled particles is indicated.

3. The area ratio of the (Ga, In) ₂ O _{3 phase is calculated.} That is, in the present invention, the area ratio of the _{(Ga, In) 2} O _{3 phase is (Ga,} in) is represented by the ratio of the total area on the ₂ O _{3 2} O ₃ a (Ga, in) calculating an area on.

(relative density)

In one embodiment, as for the sputtering target member which concerns on this invention, it is preferable that a relative density is 94 % or more, It is more preferable that it is 95 % or more, It is still more preferable that it is 95.5 % or more. The relative density of the sputtering target member is correlated with the quality of the sputtering film. When a sputtering target member is low density, there exists a possibility of generating a particle in a sputtering film by abnormal discharge or oscillation from a void|hole part. When the relative density is 94% or more, the number of internal voids becomes an acceptable range for operation, and generation of particles due to the voids can be suppressed. However, the smaller the gap is better.

In addition, the calculation method of the relative density of a sputtering target member is demonstrated below.

In the present invention, "relative density" is expressed by relative density = (measured density/calculated density) x 100 (%). A calculated density is a value of the density computed from the theoretical density of the oxide of the element except oxygen in each constituent element of a sintered compact. _{In the Ga-In-O target of the present invention, gallium oxide (Ga 2} O ₃ ) and indium oxide (In ₂ O ₃ ) are used as oxides of gallium and indium excluding oxygen among gallium, indium, and oxygen as respective constituent elements. It is used to calculate the computational density. Here, in terms of the mass ratio from the elemental analysis values of gallium and indium in the sintered product (at%, or% by weight), gallium oxide (Ga ₂ O ₃₎ and indium oxide (In ₂ O _3). For example, in terms of the result, in the case of the IGO target the gallium oxide and 50% by weight indium 50% by mass of oxide, calculated density (of Ga ₂ O ₃ Density (g / ㎤) × 50 + In 2 O 3 of It calculates as density (g/cm<3>)*50)/100 (g/cm<3>). The theoretical density of Ga ₂ O 3 is 5.95 g/cm _{3 , and the theoretical density of In 2} O ₃ is 7.18 g/cm 3 , and is calculated. On the other hand, the measured density is a value obtained by dividing the weight by the volume. In the case of a sintered compact, the volume is calculated|required and computed by the Archimedes method.

(volume resistivity)

In one embodiment of the sputtering target member according to the present invention, the volume resistivity is ^{preferably 1.0×10 3} Ω·cm or less, and 5.0×10 ² Ω·cm from the viewpoint of improving the film formation rate during sputtering. cm or less is more preferable, and 1.0×10 ² Ω·cm or less is still more preferable, and ^{can be, for example, 1.0 to 1.0×10 3} Ω·cm.

In this invention, the volume resistivity of a sputtering target member is measured by the 4 probe method using a resistivity measuring instrument. Since the altered layer by sintering exists on the surface of a sputtering target member, it grinds 1.0 mm and finishes it with the abrasive paper of the average particle diameter #400 of the abrasive grain based on JISR6010:2000. In the Example, it measured with the following apparatus.

Resistivity meter: Model FELL-TC-100-SB-Σ5+ (manufactured by NPES Co., Ltd.)

Measuring Jig: Sample Stand RG-5

In one embodiment of the sputtering target member according to the present invention, when a sputtering film is formed by changing the amount of oxygen in the sputtering gas from 0 to 3% by volume, the work function of the sputtering film is preferably in the range of 5.0 to 6.0 eV. Do. In addition, film-forming conditions are illustrated below.

<Film formation conditions>

Sputtering device: manufactured by Canon Anerva, model number: SPF-313H

Substrate: EAGLE XG (manufactured by Corning)

Input: 1W/cm2

Substrate temperature: room temperature

Reached vacuum: 2.0×10 ^-4 Torr or less

Sputter gas: Ar + oxygen (0 to 3 vol%)

Gas flow: 50sccm

Film thickness: 100 nm

The work function can be measured, for example, by photoelectron spectroscopy. In the measurement, the following apparatus and procedure are used.

An example of the device: Air photoelectron spectroscopy device AC-3 (manufactured by RIKEN KEIKI)

Procedure: After sputtering, the film-forming substrate is vacuum-packed within 10 minutes, and released to the atmosphere immediately before measurement. This is because, if stored in the air, the surface deteriorates and an accurate value cannot be obtained.

Although it is not limited as a sputtering target member, It is possible to process into shapes, such as a flat plate shape and a cylindrical shape, and to use it.

[2. Manufacturing method of sputtering target member]

Next, the manufacturing method of a sputtering target member is demonstrated using drawings. In one Embodiment, as shown in FIG. 1, the manufacturing method of the sputtering target member which concerns on this invention contains mixing process S11, pressure forming process S21, sintering process S31, and machining process S41. Hereinafter, each process is illustrated respectively. In addition, about the content which overlaps with the above-mentioned, it abbreviate|omits.

(Mixing process S11)

In the mixing step S11, it is weighed so that a raw material powder to less than Ga ₂ O ₃ powder and the In ₂ O ₃ powder than the atomic ratio of Ga / In 0.90 1.11. In order to avoid the adverse effect on the electrical properties by impurities, it is preferable to use a raw material powder having a purity of 3N (99.9 mass%) or more, and it is more preferable to use a raw material powder having a purity of 4N (99.99 mass%) or more. In addition, since the influence on the crystal phase to be purified is slight, Sn may be included as an impurity up to 1000 mass ppm.

Next, Ga ₂ O ₃ powder and In ₂ O ₃ powder are mixed and finely pulverized by wet, respectively. The mixed powder obtained by mixing and pulverizing preferably has a median diameter of 5 µm or less, more preferably 3 µm or less, and still more preferably 1 µm or less. In addition, the median diameter of the mixed powder is the median diameter (D50) based on the volume when the cumulative distribution of particle sizes is measured using a laser diffraction scattering method particle size measuring device after ultrasonic dispersion for 1 minute using ethanol as a dispersion medium. points to

However, when mixing and pulverization are insufficient, each component segregates in the produced sputtering target member, and a high resistivity region and a low resistivity region exist, and abnormal discharge such as arcing due to charging in the high resistivity region during sputter film formation It is preferable to sufficiently mix and pulverize. Suitable mixing and pulverization methods include, for example, a method of dispersing raw material powder in water to form a slurry, and pulverizing the slurry using a wet medium stirring mill (such as a bead mill). In addition, when producing a large sputtering target member, the warpage after sintering may become large, in that case, the _{powder obtained by mixing Ga 2} O ₃ powder and In ₂ O ₃ powder is calcined at 800 to 1250 ° C. It may be finely pulverized.

Next, PVA (polyvinyl alcohol) is put into the obtained slurry as a binder. The quantity of PVA is not specifically limited, It can adjust suitably.

Next, the slurry after PVA input is dried and granulated with a spray dryer to obtain a mixed powder. Although drying is not limited, For example, it can perform on 150-200 degreeC conditions. After drying, it is preferable to separate the coarse particles by sieving. The sieving is preferably carried out with a sieve of 500 µm or less, and more preferably of 250 µm or less. Here, the eye size is measured based on JIS Z8801-1:2006.

(Pressure forming step S21)

In the pressure molding process S21, the mixed powder is filled in the metal mold|die of a desired shape, and it presses and obtains a molded object. The surface pressure at the time of pressing can be 400-1000 kgf/cm<2>, for example. Moreover, you may perform a cold isostatic pressure press.

(Sintering step S31)

In the sintering step S31, for example, the molded body is sintered in an oxygen-containing atmosphere at a heating temperature exceeding 1400°C for 5 hours or more to obtain a sintered body containing a Ga-In-O composite oxide phase.

The reason for heating in an oxygen-containing atmosphere is to suppress the evaporation of oxides and to improve the density of the sintered body. As oxygen-containing atmosphere, although an oxygen atmosphere and an air atmosphere are mentioned, for example, From a viewpoint that a density improves more, an oxygen atmosphere is preferable. The reason that the heating temperature in the sintering step S31 exceeds 1400°C is that the reaction rate of sintering is sufficiently fast and (Ga, In) ₂ O ₃ is produced. As described in Patent Document 1, sintering at 1400°C or lower produces β-Ga ₂ O ₃ . That is, heating temperature exceeds 1400 degreeC as a lower limit side, It is preferable that it is 1450 degreeC or more, and it is more preferable that it is 1500 degreeC or more. On the other hand, when the temperature is too high, sintering is preferably performed at a heating temperature of less than 1600°C, more preferably 1550°C or less, from the viewpoint of a possibility of a composition shift due to volatilization of the oxide. The heating holding time at a heating temperature exceeding 1400°C is preferably 5 hours or longer in order to sufficiently advance sintering. Although the said heating holding time is more preferably 10 hours or more, since the rise of a relative density is small even if it increases the time beyond that, 20 hours or less are preferable.

(Machining process S41)

In machining process S41, the formed sintered compact is machined into a desired shape using machining machines, such as a plane grinder, a cylindrical grinder, a lathe, a cutter, and a machining center, and a sputtering target member is obtained.

[3. sputtering target]

In one Embodiment, the sputtering target which concerns on this invention joins base materials, such as the sputtering target member mentioned above, and a backing plate or a backing tube, and is used. Although the sputtering target member and the base material may be joined by any known method, it is possible to use, for example, low-melting-point solder, for example, indium solder or the like. As the material of the base material, any known material may be used, but it is possible to use, for example, copper (eg, oxygen-free copper), copper alloy, aluminum alloy, titanium, stainless steel, and the like.

[4. sputtering film]

In one embodiment, the sputtering film according to the present invention is a sputtering film formed of Ga, In, O, and unavoidable impurities, and has an atomic ratio of Ga/In of 0.85 or more and 1.15 or less. Further, the sputtering film according to the present invention is preferably amorphous in order not to leave a part of the crystallized film as a so-called etching residue.

A method of confirming the crystallinity of the sputtering film is exemplified below. When XRD is performed on the sputtering film and no specific crystal peak is observed but a broad halo pattern is observed, the sputtering film as an observation object can be said to be amorphous.

<Measurement conditions>

An example of an XRD diffractometer: Smart Lab (manufactured by Rigaku Co., Ltd.)

Tube voltage: 40kV

Tube current: 30mA

Measurement range: 2θ = 10° to 90°

Scan axis: 2θ/θ

Scan speed: 10°/min

Step Width: 0.01°

Analysis software: PDXL (supplied with Smart Lab)

(refractive index)

In one embodiment, the sputtering film according to the present invention has a refractive index of 1.9 to 2.1 at a wavelength of 633 nm. The refractive index can be measured using, for example, a spectroscopic ellipsometer.

(extinction coefficient)

In one embodiment of the sputtering film according to the present invention, the extinction coefficient at a wavelength of 633 nm is preferably 0.01 or less from the viewpoint of improving the transmittance, more preferably 0.001 or less, and still more preferably 0.0005 or less. However, the lower limit is typically 0 or more, and more typically 0.00001 or more. The extinction coefficient can be measured using, for example, a spectroscopic ellipsometer.

(work function)

In one embodiment, the sputtering film according to the present invention preferably has a work function of 5.0 to 6.0 eV. As for the work function, 5.0 eV or more is preferable as a lower limit side, 5.2 eV or more is more preferable, and 5.5 eV or more is still more preferable. Since the value of the work function varies depending on the device employed, it is not possible to determine which value is preferable uniformly, but it is desirable to be able to control it within this range. The work function can be measured, for example, by photoelectron spectroscopy. In the measurement, the following apparatus and procedure are used.

Device: Air photoelectron spectroscopy device AC-3 (manufactured by RIKEN KEIKI)

Procedure: After sputtering, the film-forming substrate is vacuum-packed within 10 minutes, and released to the atmosphere immediately before measurement. This is because, if stored in the air, the surface deteriorates and an accurate value cannot be obtained.

(volume resistivity)

In one embodiment, the sputtering film according to the present invention preferably has a volume resistivity of 1.0 ^{Ω·cm or less, more preferably 1.0×10 −1} Ω·cm or less, and more preferably 5.0×10 ^-2 Ω·cm or less. Preferably ^{, it can be set as 1.0x10 -3} -1.0 ohm*cm, for example. Thereby, it can use suitably as an electrically conductive film.

In the present invention, the volume resistivity is measured by a four-probe method using a resistivity meter. In the Example, it measured with the following apparatus.

Resistivity meter: Model FELL-TC-100-SB-Σ5+ (manufactured by NPES Co., Ltd.)

Measuring Jig: Sample Stand RG-5

[5. Manufacturing method of sputtering film]

The manufacturing method of the sputtering film which concerns on this invention includes the film-forming process of forming a sputtering film into a film using the sputtering target member mentioned above in one Embodiment. There is no restriction|limiting in particular in the sputtering apparatus which a sputtering target member can use. For example, a magnetron sputtering device, an RF applied magnetron DC sputtering device, etc. can be used.

In the film forming step, the amount of oxygen in the sputtering gas is preferably 10% by volume or less, more preferably 5% by volume or less, and 3% by volume or less, from the viewpoint of obtaining a sputtering film having a low volume resistivity. It is more preferable to do In addition, the amount of oxygen in the sputtering gas is preferably carried out at 0% by volume or more, and if oxygen is not included, it is more preferable to carry out at 1% by volume or more, from the viewpoint that the work function tends to be low when oxygen is not included. % or more is more preferable.

After the film-forming process, in order to make the volume resistivity small, you may further include the process of annealing a sputtering film. In addition, in a film-forming process, you may form a sputtering film into a film, annealing. As conditions for annealing, carrying out over 0.2 to 5 hours at 60-200 degreeC in air|atmosphere, for example is mentioned, for example.

[6. laminated structure]

It is sectional drawing for demonstrating one Embodiment of the laminated structure which concerns on this invention. 3 to 7 are cross-sectional views for explaining another embodiment of the laminated structure according to the present invention. EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of the laminated structure which concerns on this invention is demonstrated using drawings.

2 to 7 , the laminated structures 10A, 10B, 10C, 10D, 10E, and 10F include a second metal film 11 , an organic layer 12 , a film body 13 , and a substrate. (14) is provided.

The second metal film 11 is in contact with the main surface 12-1 of the organic layer 12 on the opposite side to the film body 13 . The second metal film has a role as a cathode, for example, when used as an organic EL device. The second metal film 11 is not particularly limited as long as it is a metal, but from the viewpoint of using a metal having a low work function to facilitate electron injection and increase luminous efficiency, Al, In, W, Ti, Mo, Mg- It is preferable that it is formed of 1 type or 2 or more types selected from the group which consists of Ag and Ag-Al. For example, the second metal film 11 is formed by a vacuum deposition method or a sputtering method. Further, the thickness of the second metal film 11 is typically 5 to 20 nm, more typically 7 to 17 nm.

The organic layer 12 is in contact with the second main surface 13a-2 opposite to the first main surface 13a-1 of the sputtering film 13a. The organic layer 12 includes an organic hole transport layer and an organic light emitting layer, an organic hole transport layer is provided on the sputtering film 13a, and an organic light emitting layer is provided on the organic hole transport layer.

The film body 13 has, for example, a role as an anode when used as an organic EL device. The film body 13 shown in FIG. 2 is provided with the sputtering film 13a mentioned above. The film body 13 shown in Fig. 3 includes a sputtering film 13a and a first metal film 13b in contact with the first main surface 13a-1 of the sputtering film 13a. The film body 13 shown in Fig. 4 includes a sputtering film 13a, a first metal film 13b in contact with the first main surface 13a-1 of the sputtering film 13a, and a first metal film 13b. ), an oxide barrier film 13c in contact with the main surface 13b-1 is provided. The film body 13 shown in Fig. 5 includes a sputtering film 13a and an oxide conductive film 13d in contact with the first main surface 13a-1 of the sputtering film 13a. The film body 13 shown in Fig. 6 includes a sputtering film 13a, an oxide conductive film 13d in contact with the first main surface 13a-1 of the sputtering film 13a, and the main oxide conductive film 13d. A first metal film 13b in contact with the surface 13d-1 is provided. The film body 13 shown in Fig. 7 includes a sputtering film 13a, an oxide conductive film 13d in contact with the first main surface 13a-1 of the sputtering film 13a, and an oxide conductive film 13d. A first metal film 13b in contact with the main surface 13d-1 and an oxide barrier film 13c in contact with the main surface 13b-1 of the first metal film 13b are provided.

As described above, the sputtering film 13a has a high work function. It forms into a film on the 1st metal film 13b or the oxide conductive film 13d by the sputtering method using the sputtering target member mentioned above. Of course, when manufacturing the organic EL device mentioned later, you may form into a film on the board|substrate 14, such as a glass substrate or a resin substrate, without forming into a film on the 1st metal film 13b. The thickness of the sputtering film 13a is typically 1 to 20 nm, and more typically 2 to 10 nm.

The first metal film 13b is not particularly limited, but is selected from the group consisting of Ag, Cu, Ni, Fe, Cr, Al and Co from the viewpoint of using a metal having excellent reflectance and high conductivity. It is preferable to form by the composition containing 90 mass % or more of types or 2 or more types. For example, the first metal film 13b is formed by a vacuum deposition method or a sputtering method. The thickness of the first metal film 13b is typically 10 to 200 nm, and more typically 20 to 150 nm.

The oxide barrier film 13c is not particularly limited, but from the viewpoint of preventing oxidation or corrosion of the first metal film 13b, Al, Mg, Si, Sn, Zr, Ti, Ga, Nb, Ta, Hf , W, Zn and In are preferably formed of an oxide or nitride of an element selected from one or two or more selected from the group consisting of. The thickness of the oxide barrier film 13c is typically 5 to 100 nm, and more typically 10 to 60 nm.

Although the oxide conductive film 13d is not particularly limited, it is preferably formed of one or two or more selected from the group consisting of ITO, IZO and AZO, having high conductivity of ^{1.0×10 -3 Ω·cm or less.} Do. The thickness of the oxide conductive film 13d is typically 1 to 20 nm, and more typically 2 to 10 nm. In addition, by disposing the oxide conductive film 13d, better conductivity can be obtained without disposing the first metal film 13b.

When the oxide conductive film (13d) are formed of ITO is, for example, mainly composed of In ₂ O _3, and including from 5 to 15% by weight of Sn in terms of SnO _2.

If the oxide conductive film (13d) are formed as IZO it is, for example, mainly composed of In ₂ O _3, and containing 2.5 to 15% by weight of Zn in terms of ZnO.

If the oxide conductive layer (13d) is formed to include AZO, for example, containing mainly ZnO, and 0.5 to 10% by weight of Al in terms of Al ₂ O _3.

The substrate 14 is in contact with the outermost main surface of the film body 13 on the first main surface 13a-1 side of the sputtering film 13a. Here, the outermost main surface of the film body 13 is represented by the first main surface 13a-1 of the sputtering film 13a shown in FIG. 2, and the main surface of the first metal film 13b shown in FIG. It is denoted by the surface 13b-1, denoted by the main surface 13c-1 of the oxide barrier film 13c shown in Fig. 4, and the main surface 13d- of the oxide conductive film 13d shown in Fig. 5. 1), denoted by the main surface 13b-1 of the first metal film 13b shown in Fig. 6, and denoted by the main surface 13d-1 of the oxide conductive film 13d shown in Fig. 7 do. Moreover, as the board|substrate 14, a glass substrate or a resin substrate is mentioned, for example.

The laminated structures 10A, 10B, 10C, 10D, 10E, and 10F can be used for a top emission type organic EL device. More specifically, in the organic EL device (not shown), a sealing layer, a laminated structure, a thin film transistor (TFT), and a substrate are laminated in this order. When a voltage is applied to the lower electrode and the upper electrode by the driving circuit, electrons from the upper electrode and holes from the lower electrode flow into the organic layer 12 , and electrons and holes recombine by the light emitting molecules of the organic layer 12 . glow The light from the organic layer 12 is extracted from the sealing layer side on the opposite side to the board|substrate.

[Example]

The present invention will be specifically described based on Examples and Comparative Examples. The following examples and comparative examples are specific examples for facilitating the understanding of the technical content of the present invention to the last, and the technical scope of the present invention is not limited by these specific examples.

(Example 1)

After weighing the commercially available Ga ₂ O ₃ powder and In ₂ O ₃ powder so as to have an atomic ratio of Ga/In shown in Table 1, these powders are mixed and finely pulverized by wet, and then dried with a spray dryer. granulation to obtain a mixed powder.

Next, this mixed powder was filled in a mold and press-molded (surface pressure: 300 kgf/cm 2 , holding time: 1 minute) with a press to prepare a molded article having a thickness of 13 mm. Thereafter, the obtained molded article was subjected to CIP molding (surface pressure: 1500 kgf/cm 2 , holding time: 20 minutes).

Next, the obtained compact was charged into a sintering furnace and sintered at a temperature of 1500°C in an oxygen atmosphere for 10 hours, and then naturally cooled to room temperature to obtain a sintered compact having a thickness of 10 mm.

And the upper surface, the lower surface, and the side surface of the obtained sintered compact were cut by machining, and each surface was ground with a plane grinding machine, and the flat plate-shaped sputtering target member of (phi) 203.2 mm x 5 mmt was obtained. Evaluation shown below was performed about the obtained sputtering target member, respectively.

<EPMA analysis>

As described above, as a result of observing the structure of the sputtering target member using an electron beam microanalyzer, as shown in Fig. 8A, (Ga, In) ₂ O ₃ phases composed of Ga, In, and O are formed, confirmed that there is. In addition, the area ratio was calculated|required by the method mentioned above about the said (Ga, In) ₂ O _{3 phase.} In addition, the area ratio is shown in Table 1.

<relative density>

The measured density of the sputtering target member used as a measurement object was calculated|required by Archimedes' method, and the relative density was calculated|required by relative density = measured density/calculated density. In addition, the relative density is shown in Table 1.

<crystal phase>

About a sputtering target member, it determined by performing X-ray-diffraction measurement (XRD) by the method mentioned above. As a result, the XRD graph shown in FIG. 8(B) was obtained. According to ICDD, (Ga, In) ₂ O ₃ of No. 00-014-0564, Ga ₂ In ₆ Sn ₂ O ₁₆ of No. 00-051-0205, and Ga _{2.4 of No. 00-051-0204} In _5.6 Sn ₂ O ₁₆ , In ₂ O ₃ of No. 01-089-4595, and Ga ₂ O ₃ of No. 01-087-1901 were observed.

<Volume resistivity>

The volume resistivity of the sputtering target member was measured by the method mentioned above using the resistivity measuring instrument (NPS Co., Ltd. make, model FELL-TC-100-SB-Sigma 5+, measuring jig RG-5) using the DC 4 probe method. . In addition, the volume resistivity is shown in Table 1.

<Composition>

The sputtering target member was subjected to ICP emission spectroscopy (high frequency inductively coupled plasma emission spectrometry). A part of a sputtering target member was made into a sample, it melt|dissolved with an acid, it diluted with ultrapure water, and it was set as the measurement sample. Each metal element was analyzed for this solution. As a result, Ga and In among each metal element were substantially equal to the atomic ratio of Ga and In calculated from the mixing ratio of _{Ga 2} O ₃ powder and In ₂ O _{3 powder.} Moreover, although Sn was a trace amount, several hundred mass ppm was detected.

Next, the obtained sputtering target member was bonded to the copper backing plate with indium solder, and the sputtering target was obtained. This sputtering target was respectively formed into a film by a DC (direct current) sputtering apparatus under the conditions of containing 0 volume%, 1 volume%, 2 volume%, and 3 volume% of oxygen in argon gas according to the film-forming conditions mentioned above.

<work function>

The work function of the sputtering film obtained at 0% by volume to 3% by volume of oxygen was measured at two arbitrarily selected locations by the above-described method using an atmospheric photoelectron spectrometer AC-3 (manufactured by RIKEN KEIKI). The average value of the measured values was used as a work function.

<Refractive Index>

The refractive index of the sputtering film was measured with a spectroscopic ellipsometer (manufactured by J. A. Woollam, model number: ESM-300), and a value having a wavelength of 633 nm was used. Moreover, after the sputtering film was annealed at 150 degreeC over 1 hour in air|atmosphere, the refractive index of the sputtering film after the process was also measured.

<Extinction coefficient>

The extinction coefficient of the sputtering film was measured with a spectroscopic ellipsometer (manufactured by J. A. Woollam, model number: ESM-300), and a value having a wavelength of 633 nm was used. Moreover, after the sputtering film was annealed at 150 degreeC over 1 hour in air|atmosphere, the extinction coefficient of the sputtering film after the process was also measured.

<Volume resistivity of thin film>

The volume resistivity of the surface of the sputtering film was measured by the method described above using a resistivity measuring instrument using a DC 4 probe method (manufactured by NPS, Inc., model FELL-TC-100-SB-Σ5+, measuring jig RG-5). . Moreover, after the sputtering film was annealed at 150 degreeC over 1 hour in air|atmosphere, the volume resistivity of the sputtering film after the process was also measured.

<Crystallinity>

The crystallinity of the sputtering film was observed by the method described above. In addition, after the sputtering film was annealed at 150°C for 1 hour in the air, the crystallinity of the sputtered film after the treatment was also observed.

(Example 2)

In Example 2, it carried out similarly to Example 1 except having changed the atomic ratio of Ga/In to 0.905. In addition, the manufacturing conditions and evaluation result of a sputtering target member are shown in Table 1, and the evaluation result of a sputtering film is shown in Table 2.

(Example 3)

In Example 3, it carried out similarly to Example 1 except having changed the atomic ratio of Ga/In to 1.105. In addition, the manufacturing conditions and evaluation result of a sputtering target member are shown in Table 1, and the evaluation result of a sputtering film is shown in Table 2.

(Example 4)

In Example 4, it implemented similarly to Example 1 except having changed the sintering conditions into air|atmosphere. In addition, the manufacturing conditions and evaluation result of a sputtering target member are shown in Table 1, and the evaluation result of a sputtering film is shown in Table 2.

(Example 5)

In Example 5, it implemented similarly to Example 1 except having changed the sintering temperature to 1550 degreeC. In addition, the manufacturing conditions and evaluation result of a sputtering target member are shown in Table 1, and the evaluation result of a sputtering film is shown in Table 2.

(Example 6)

In Example 6, it implemented similarly to Example 1 except having changed the sintering temperature to 1450 degreeC. In addition, the manufacturing conditions and evaluation result of a sputtering target member are shown in Table 1, and the evaluation result of a sputtering film is shown in Table 2.

(Comparative Example 1)

In Comparative Example 1, it carried out similarly to Example 1 except having changed the sintering temperature to 1400 degreeC. In addition, the manufacturing conditions and evaluation result of a sputtering target member are shown in Table 1, and the evaluation result of a sputtering film is shown in Table 2.

(Comparative Example 2)

In the comparative example 2, it implemented similarly to Example 1 except having changed the sintering temperature to 1600 degreeC. Since the sintered compact had reacted with the bottom plate, the sputtering target member could not be produced. In addition, the manufacturing conditions of a sputtering target member are shown in Table 1.

(Comparative Example 3)

In Comparative Example 3, the same procedure as in Example 1 was carried out except that the Ga/In atomic ratio was changed to 0.667. In addition, the manufacturing conditions and evaluation result of a sputtering target member are shown in Table 1, and the evaluation result of a sputtering film is shown in Table 2.

(Comparative Example 4)

In Comparative Example 4, the same procedure as in Example 1 was carried out except that the Ga/In atomic ratio was changed to 1.500. In addition, the manufacturing conditions and evaluation result of a sputtering target member are shown in Table 1, and the evaluation result of a sputtering film is shown in Table 2.

(Consideration by Example)

The sputtering films produced in Examples 1 to 6 had a work function of 5.0 to 6.0 eV and a refractive index of 1.9 to 2.1 at a wavelength of 633 nm, so it is considered useful for use in an organic EL device.

In Comparative Example 1, since the sintering temperature was low, the target refractive index was not obtained. In Comparative Example 3, since Ga/In was low, _{relatively many In 2} O ₃ phases having a bixbite structure were formed in the crystal phase. As a result, compared with Examples 1 to 6, the work function was low, and the target refractive index was not obtained. In Comparative Example 4, since Ga/In was high, _{relatively many β-GaInO 3} phases were formed in the crystal phase. As a result, compared with Examples 1 to 6, the volume resistivity was high and the work function was low, and the target refractive index was not obtained.

10A, 10B, 10C, 10D, 10E, 10F: laminated structure
11: second metal film
12: organic layer
12-1: main surface
13: makche
13a: sputtering film
13a-1: first major surface
13a-2: second major surface
13b: first metal film
13b-1: major surface
13c: oxide barrier film
13c-1: major surface
13d: oxide conductive film
13d-1: major surface
14: substrate
S11: mixing process
S21: filling process
S31: sintering process
S41: Machining process

Claims (37)

It is a sputtering target member formed of Ga, In, O and unavoidable impurities,
The atomic ratio of Ga/In is 0.90 or more and 1.11 or less, and in the plane analysis in EPMA, (Ga, In) ₂ O _{3 with respect to the entire crystal phase} The sputtering target member whose area ratio of an image is 90 % or more. According to claim 1,
The sputtering target member whose atomic ratio of the said Ga/In is 0.95 or more and 1.05 or less. According to claim 1,
The sputtering target member whose said area ratio is 95 % or more. 3. The method of claim 2,
The sputtering target member whose said area ratio is 95 % or more. 5. The method according to any one of claims 1 to 4,
The sputtering target member whose relative density is 94 % or more. 5. The method according to any one of claims 1 to 4,
A sputtering target member having a volume resistivity of 1.0×10 ³ Ω·cm or less. 6. The method of claim 5,
A sputtering target member having a volume resistivity of 1.0×10 ³ Ω·cm or less. 5. The method according to any one of claims 1 to 4,
A sputtering target member whose work function is in the range of 5.0-6.0 eV, when a sputtering film is formed into a film by changing the amount of oxygen in sputtering gas from 0 to 3 volume%. 5. The method according to any one of claims 1 to 4,
A sputtering target member having a cylindrical shape or a flat plate shape. The sputtering target provided with the sputtering target member in any one of Claims 1-4, and a base material. It is the manufacturing method of the sputtering target member in any one of Claims 1-4,
A _{mixing step of mixing In 2} O ₃ powder and Ga ₂ O ₃ powder so that an atomic ratio of Ga/In is 0.90 or more and 1.11 or less to obtain a mixed powder;
The manufacturing method of the sputtering target member including the sintering process of sintering the said mixed powder at sintering temperature exceeding 1400 degreeC and less than 1600 degreeC, and obtaining a sintered compact. 12. The method of claim 11,
The manufacturing method of the sputtering target member whose said sintering temperature is 1450 degreeC - 1550 degreeC. 12. The method of claim 11,
The said sintering process WHEREIN: The manufacturing method of a sputtering target member whose sintering holding time is 5 to 20 hours. A sputtering film produced using the sputtering target member according to any one of claims 1 to 4, wherein it is a sputtering film formed of Ga, In, O, and unavoidable impurities,
A sputtering film having an atomic ratio of Ga/In of 0.85 or more and 1.15 or less, a refractive index of 1.9 to 2.1 at a wavelength of 633 nm, and a work function of 5.0 to 6.0 eV. 15. The method of claim 14,
The sputtering film whose volume resistivity is 1.0 ohm*cm or less. 15. The method of claim 14,
The sputtering film whose extinction coefficient in wavelength 633nm is 0.01 or less. 16. The method of claim 15,
The sputtering film whose extinction coefficient in wavelength 633nm is 0.01 or less. 15. The method of claim 14,
Amorphous, sputtered film. The manufacturing method of a sputtering film including the film-forming process of forming a sputtering film into a film using the sputtering target member in any one of Claims 1-4. The manufacturing method of a sputtering film including the film-forming process of forming a sputtering film into a film using the sputtering target of Claim 10. 20. The method of claim 19,
After the film-forming process, the manufacturing method of the sputtering film including the process of annealing the said sputtering film|membrane at 200 degrees C or less. 20. The method of claim 19,
In the film forming step, the sputtering film is formed while annealing at 200°C or lower. 20. The method of claim 19,
In the said film-forming process, the manufacturing method of a sputtering film which implements the amount of oxygen in sputtering gas to 10 volume% or less. A film body provided with the sputtering film|membrane of Claim 14. 25. The method of claim 24,
The film body further comprising a first metal film in contact with the first main surface of the sputtering film. 26. The method of claim 25,
The film body further comprising an oxide barrier film in contact with the main surface of the first metal film. 25. The method of claim 24,
A film body comprising an oxide conductive film in contact with a first main surface of the sputtering film. 28. The method of claim 27,
The film body further comprising a first metal film in contact with the main surface of the oxide conductive film. 29. The method of claim 28,
The film body further comprising an oxide barrier film in contact with the main surface of the first metal film. 28. The method of claim 27,
The film body, wherein the oxide conductive film has a volume resistivity of 1.0×10 ^-3 Ω·cm or less. 28. The method of claim 27,
The said oxide conductive film is formed with at least 1 sort(s) selected from the group of ITO, IZO, and AZO. 26. The method of claim 25,
The said 1st metal film|membrane was formed with the composition containing 90 mass % or more of 1 type(s) or 2 or more types selected from the group of Ag, Cu, Ni, Fe, Cr, Al, and Co. The membrane according to claim 24,
A laminated structure comprising a glass substrate or a resin substrate in contact with the outermost major surface of the film body on the first major surface side of the sputtering film. 34. The method of claim 33,
and an organic layer in contact with a second main surface opposite to the first main surface of the sputtering film. 35. The method of claim 34,
A laminated structure further comprising a second metal film in contact with the main surface of the organic layer. 36. The method of claim 35,
The second metal film is formed of one or two or more selected from the group consisting of Al, In, W, Ti, Mo, Mg-Ag, and Ag-Al. An organic EL device in which a sealing layer, the laminate structure according to claim 33, a thin film transistor, and a substrate are laminated in this order.

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