KR20210082410A - Sputtering target and manufacturing method thereof - Google Patents

Abstract

In a Ga-Sn-O-based sputtering target member containing a high concentration of Ga, provided is an effective means for lowering the bulk resistivity (equivalent to the volume resistivity). According to the present invention, the sputtering target member contains Ga, Sn and O, and has the remainder composed of unavoidable impurities, and the atomic ratio of Ga and Sn satisfies 0.33 <= Ga/(Ga+Sn) <= 0.75. The sputtering target member has a ratio (I_(Sn)/I) of the SnO_2 phase peak area (I_(Sn)) to the total peak area (I) in powder X-ray diffraction measurement of 0.02 or more.

Description

A sputtering target member and its manufacturing method TECHNICAL FIELD

This invention relates to a Ga-Sn-O type|system|group sputtering target member and its manufacturing method.

Conventionally, silicon-based materials such as polycrystalline silicon films and amorphous silicon films have been used as semiconductor layers used in the channel layers of thin film transistors (TFTs). However, since the silicon-based material absorbs in the visible light region, there is a problem in that the thin film transistor malfunctions due to the generation of carriers due to light incident. As a preventative measure, a light blocking layer such as a metal is provided, but there is a problem that the aperture ratio decreases. Moreover, in order to maintain the brightness|luminance of a screen, there existed a fault, such as a high brightness|luminance increase of a backlight is required and power consumption increases.

Here, in recent years, a thin film transistor using a transparent oxide semiconductor has been developed instead of a silicon-based material. A typical example thereof is an In-Ga-Zn-O-based (IGZO) material (Patent Document 1). However, since IGZO is a multi-component system, it is difficult to optimize the properties and state of each raw material powder, mixing of components, and sintering conditions. Therefore, the properties of IGZO are liable to fluctuate, and the point causing nodules and abnormal discharge during sputtering was considered a problem. Moreover, since IGZO contains a rare metal, it becomes a factor which raises cost, and there exists a possibility that supply may become insufficient in the future.

Against this background, Ga-Sn-O-based (GTO) oxide targets with few constituent elements have been studied (Patent Documents 2-3).

International Publication No. 2005/088726 International Publication No. 2010/018707 Japanese Patent Laid-Open No. 2013-40394

However, in the oxide sintered body described in Patent Document 2, in addition to the gallium stannate compound phase and the tin oxide phase in order to increase the strength of the sintered body and reduce bulk resistance, zinc, aluminum, silicon, indium, germanium, titanium, niobium, At least one element selected from tantalum, tungsten, molybdenum and antimony is required to be dispersed. And in patent document 2, when only gallium oxide and tin oxide were used as raw materials, when gallium oxide concentration was high, it is shown that bulk resistance became high to an unmeasurable degree (Comparative Examples 1, 4, 6, and 7).

In addition, Patent Document 3 describes an oxide sintered target for sputtering composed of gallium (Ga), tin (Sn), oxygen (O) and unavoidable impurities, but _{the concentration of Ga 2} O ₃ is required to be 20 mol% or less, have. Patent Document 3 shows that when _{the concentration of Ga 2} O ₃ is 30 mol%, the bulk resistivity is increased to such an extent that it cannot be measured (Comparative Examples 4 and 5).

Thus, in the Ga-Sn-O type|system|group sputtering target member containing high concentration Ga, the thing with low bulk resistivity suitable for DC sputtering was not obtained. The present invention was created in view of the above circumstances, and in one embodiment, in a Ga-Sn-O-based sputtering target member containing a high concentration of Ga, to provide an effective means for lowering the bulk resistivity (equivalent to "volume resistivity") make it one task.

The present inventor analyzed the crystal structure of a Ga-Sn-O-based sputtering target member containing a high concentration of Ga by powder XRD, and found that many complex oxide phases of Ga and Sn can be seen, while the amount of tin oxide phase is very small. found that And as a result of repeated studies based on this knowledge, in the Ga-Sn-O type sputtering target member, if the ratio of the composite oxide phase of Ga and Sn is lowered and the ratio of the tin oxide phase is increased, the volume resistivity is reduced even when the overall composition is the same. found to be significantly lowered.

This invention was completed based on the said knowledge, and is illustrated as follows.

[One]

It contains Ga, Sn and O, the remainder is composed of unavoidable impurities, the atomic ratio of Ga and Sn satisfies 0.33≤Ga/(Ga+Sn)≤0.75, and the total peak area (I) in powder X-ray diffraction measurement A sputtering target member having a ratio (I _Sn /I) of the peak area (I _Sn ) of the SnO ₂ phase to 0.02 or more.

[2]

The sputtering target member according to [1], wherein the ratio (I _Sn /I) of the peak area (I _{Sn ) of the SnO 2} phase to the total peak area (I) in the powder X-ray diffraction measurement is 0.1 or more.

[3]

The sputtering target member according to [1] or [2], _wherein the ratio (I GaSn /I) of the peak area (I _{GaSn ) of the Ga 4} SnO ₈ phase to the total peak area (I) in the powder X-ray diffraction measurement is 0.3 or less. .

[4]

The sputtering target member according to [3], _wherein the ratio (I GaSn /I) of the peak area (I _{GaSn ) of the Ga 4} SnO ₈ phase to the total peak area (I) in the powder X-ray diffraction measurement is 0.25 or less.

[5]

The sputtering target member according to any one of [1] to [4], wherein the volume resistivity is 50,000 Ω·cm or less.

[6]

The sputtering target member according to any one of [1] to [5], wherein the relative density is 94% or more.

[7]

By the step of, Ga ₂ O ₃ powder and the SnO ₂ powder so that the Ga ₂ O ₃ powder in the mixed powder, the molar concentration of less than 60mol% 20mol% or more mixing and grinding the mixed powder prepared, and 1,

Step 2 of sintering the mixed powder in an oxygen-containing atmosphere at a heating temperature of 1500° C. or more for 10 hours or more to obtain a sintered body containing a Ga-Sn-O composite oxide phase;

Step 3, in which the sintered body is annealed at a heating temperature of 1000° C. to 1400° C. for 10 hours or more to decompose the Ga-Sn-O composite oxide _{phase and generate a SnO 2 phase in a nitrogen-containing atmosphere;}

The manufacturing method of the sputtering target member in any one of [1]-[6] containing.

[8]

The manufacturing method of the sputtering target member as described in [7] which implements the process 2 and the process 3 continuously as it reduces to the heating temperature in the process 3 from the heating temperature in process 2.

[9]

Step 3 is the method for manufacturing a sputtering target member according to [7] or [8], wherein the step 3 is annealed at a heating temperature of 1200°C to 1400°C.

[10]

A film-forming method comprising sputtering the sputtering target member according to any one of [1] to [6].

ADVANTAGE OF THE INVENTION According to one Embodiment of this invention, although a gallium concentration is high, it becomes possible to obtain the Ga-Sn-O type|system|group sputtering target member of a low volume resistivity. Moreover, according to one Embodiment of this invention, the high gallium concentration Ga-Sn-O type|system|group sputtering target suitable for DC sputtering can be provided.

(1. Composition)

The sputtering target member which concerns on this invention contains Ga, Sn, and O in one Embodiment, and remainder is comprised with an unavoidable impurity. An unavoidable impurity usually exists in the raw material of a metal product or is unavoidably mixed in a manufacturing process. Although it is originally unnecessary, it is an acceptable impurity because it is trace amount and does not affect the characteristic of a metal product. The total amount of unavoidable impurities in the sputtering target member which concerns on this invention is generally 5000 mass ppm or less, Typically, it is 3000 mass ppm or less, More typically, it is 2000 mass ppm or less.

In one embodiment of the sputtering target member according to the present invention, the atomic ratio of Ga and Sn satisfies 0.33≤Ga/(Ga+Sn)≤0.75. 0.33≤Ga/(Ga+Sn) is because an object of the present invention is to provide a Ga-Sn-O-based sputtering target member containing a high concentration of Ga in one embodiment. It is also possible to set it as 0.4<=Ga/(Ga+Sn), and it is also possible to set it as 0.5<=Ga/(Ga+Sn). Moreover, the reason that Ga/(Ga+Sn) <=0.75 was made is the reason that it is easy to obtain the sputtering target of low volume resistivity. From the viewpoint of lowering the volume resistivity, preferably Ga/(Ga+Sn)≤0.7, more preferably Ga/(Ga+Sn)≤0.5.

In one Embodiment of the sputtering target member which concerns on this invention, Ga and Sn may exist in the form of an oxide. Examples of the oxide include gallium oxide (Ga ₂ O ₃ ), tin oxide (SnO ₂ ), and complex oxides of Ga and Sn (eg, Ga ₄ SnO ₈ , Ga ₄ Sn ₅ O ₁₆ and Ga ₃ Sn ₄ O ₁₂ ). .

(2. XRD measurement)

In order to effectively lower the volume resistivity of the sputtering target member, the ratio (I _Sn /I) of the peak area (I _{Sn ) of the SnO 2} phase to the total peak area (I) in the powder X-ray diffraction measurement is preferably 0.02 or more, It is more preferably 0.05 or more, more preferably 0.10 or more, still more preferably 0.15 or more, and still more preferably 0.20 or more. The upper limit of I _Sn /I is not particularly set, but is generally 0.40 or less, and typically 0.30 or less.

In order to effectively lower the volume resistivity of the sputtering target member, the ratio (I _GaSn /I) of the peak area (I _{GaSn ) of the Ga 4} SnO ₈ phase to the total peak area (I) in the powder X-ray diffraction measurement (I GaSn /I) is preferably 0.30 or less And, it is more preferable that it is 0.25 or less, and it is still more preferable that it is 0.20 or less. _{The lower limit of IGaSn} /I is not particularly set, but is generally 0.05 or more, and typically 0.10 or more.

XRD measurement is performed in the following procedure. The sputtering target member to be measured is pulverized to form a powder, the powder under the sieve separated by sieving with a sieve of 100 μm is pulverized to obtain a measurement sample, and a tube voltage: 40 kV by powder X-ray diffraction method, An X-ray diffraction chart in which the horizontal axis is 2θ and the vertical axis is X-ray intensity (cps) is obtained under the conditions of tube current: 30 mA, scan speed: 5°/min, and step: 0.02°. Next, the obtained X-ray diffraction chart is subjected to data processing of Kα2 removal and background removal according to the Sonneveld-Visser method.

And according to the following criteria, I _sn , I _GaSn and I are calculated|required, and I _Sn /I and I _GaSn /I are computed.

The peak area (I _{sn ) of the SnO 2} phase represents the sum of the peak areas in each of the ranges of 2θ=26.2° to 26.9°, 33.5° to 44.2°, and 51.4° to 52.0°.

The peak area (I _{GaSn ) of the Ga 4} SnO ₈ phase represents the sum of the peak areas in each of the ranges of 2θ = 14.2˚ to 14.8˚, 25.1˚ to 25.8˚, 34.5˚ to 35.0˚, and 52.9˚ to 53.5˚.

The total peak area (I) represents the sum of the peak areas in the range of 2θ = 10° to 60°.

Each peak area is the maximum peak intensity (I _max ) of each peak in the above angle range (the height from where cps is 0 to the maximum peak intensity after background removal (unit: cps)), the half-width of the peak (Wh) ( It is calculated by multiplying the peak width (unit: 2θ) at the position where the intensity becomes I _{max /2.}

(3. Volume resistivity)

In one embodiment, the sputtering target member according to the present invention has a volume resistivity of 50,000 Ω·cm or less. The low resistance of the sputtering target member can contribute to the stability of sputtering. The volume resistivity is preferably 25,000 Ω·cm or less, more preferably 15,000 Ω·cm or less, and can be, for example, 5,000 to 50,000 Ω·cm.

Let the volume resistivity be an average value at the time of measuring so that the volume resistivity of 5 arbitrary points of the sputtering target member used as a measurement object may not be biased to a measurement location using the DC 4 probe method.

(4. Relative Density)

It is preferable that the relative density of a sputtering target member is high at the point which affects volume resistivity. It is preferable that the relative density of a sputtering target member is high also from a viewpoint of suppressing that a crack and a crack generate|occur|produce in a sputtering target member. The sputtering target member according to the present invention has a relative density of 94% or more in one embodiment. The relative density is preferably 95% or more, more preferably 98% or more, and can be, for example, 94 to 98%.

In the present invention, "relative density" is expressed as relative density = (measured density/theoretical density) x 100 (%). A theoretical density is the 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. _{If the Ga-Sn-O target of the present invention is gallium oxide (Ga 2} O ₃ ) and tin oxide (SnO ₂ ) as gallium and tin oxides excluding oxygen among the constituent elements gallium, tin, and oxygen, the theoretical density is calculated. use it Here, the conversion from the element analysis of the gallium and tin in the sintered product (at%, or% by weight) at a mass ratio of gallium oxide (Ga ₂ O ₃₎ and tin oxide (SnO _2). For example, as a result of conversion, in the case of a GTO target whose gallium oxide is 25 mass % and tin oxide is 75 mass %, the theoretical density is (Ga ₂ O ₃ density (g/cm ³ ) x 25+SnO ₂ density (g) /cm ³ )×75)/100 (g/cm ³ ) is calculated. Theoretical density of the Ga ₂ O ₃ are theoretical density of 6.44g / cm ^3, SnO ₂ is calculated as 6.95g / cm ^3. 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.

(5. Manufacturing method)

Hereinafter, the preferable manufacturing method of the sputtering target member which concerns on this invention is demonstrated exemplarily. As raw material powder, gallium oxide (Ga ₂ O ₃ ) powder and tin oxide (SnO ₂ ) powder are prepared. In order to avoid adverse effects on the electrical properties due to impurities, it is preferable to use a raw material powder having a purity of 3N (99.9% by mass) or more, more preferably using a raw material powder having a purity of 4N (99.99% by mass) or more.

Next, Ga ₂ O ₃ powder and SnO ₂ powder are mixed and pulverized in a predetermined molar ratio to prepare a mixed powder. _{Ga 2} O ₃ powder and SnO ₂ powder are mixed so that the atomic ratio of Ga and Sn in the mixed powder satisfies the above 0.33≤Ga/(Ga+Sn)≤0.75. _{Specifically, it is preferable that the Ga 2} O ₃ powder in the mixed powder is 20 mol% or more. From the viewpoint of providing a Ga-Sn-O-based sputtering target member containing a high concentration of Ga, the Ga ₂ O ₃ powder in the mixed powder can be 30 mol% or more, and the Ga ₂ O ₃ powder in the mixed powder is 40 mol% It is also possible to do more than that. Further, in the viewpoint of lowering the volume resistivity of the sputtering target can be obtained, and a Ga ₂ O ₃ powder in the mixed powder is less than 60mol%, it is possible that the Ga ₂ O ₃ powder in the mixed powder is less than 55mol%.

If mixing and pulverization are insufficient, each component is segregated in the produced sputtering target member, so that a high resistivity region and a low resistivity region exist, and abnormalities such as arc caused by charging in the high resistivity region during sputter film formation Since it causes electric discharge, it is preferable to sufficiently perform mixing and pulverization. Preferred mixing and pulverizing methods include, for example, a method in which raw material powder is dispersed in water to form a slurry, and the slurry is finely pulverized using a wet medium stirring mill (such as a bead mill).

It is preferable that the slurry after pulverization be dried. Although drying is not limited, For example, it can implement on the conditions of 100-150 degreeC x 5-48 hr with a hot-air dryer. After drying, it is preferable to separate by sieving to separate coarse particles. It is preferable to set it as a sieve size of 500 micrometers or less, and, as for separating by sieve, it is more preferable to set it as a sieve size 250 micrometers or less. Here, the body size is measured based on JIS Z8801-1:2006.

The mixed powder obtained by mixing and pulverization preferably has a median diameter of 5 µm or less, more preferably 3 µm or less, and still more preferably 1 µm or less.

The median diameter of the mixed powder represents the median diameter (D50) according to 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.

Then, a molded article is produced by filling a mold of a desired shape with the mixed powder and pressing. The surface pressure at the time of pressing can be 400-1000kgf*cm<^2> , for example.

*Then, the compact is sintered at a heating temperature of 1500°C or higher for 10 hours or longer in an oxygen-containing atmosphere to obtain a sintered compact containing a Ga-Sn-O composite oxide phase. The reason that heating is performed in an oxygen-containing atmosphere is because the density of the sintered body is improved by suppressing the evaporation of _{SnO 2 .} Examples of the oxygen-containing atmosphere include an oxygen atmosphere and an air atmosphere. The reason that the heating temperature in the sintering step was set to 1500°C or higher is because the reaction rate of sintering is sufficiently fast. 1550 degreeC or more is preferable and, as for the heating temperature in a sintering process, 1600 degreeC or more is more preferable. The reason that the heating time at a heating temperature of 1500°C or higher was set to 10 hours or longer is to sufficiently advance sintering. 15 hours or more are preferable and, as for the said heating time, 20 hours or more are more preferable.

If a predetermined annealing process is performed after the sintering process, the Ga-Sn-O composite oxide phase is decomposed to form a SnO ₂ phase. Accordingly, _{the proportion of the SnO 2} phase increases, and the volume resistivity decreases significantly. It is preferable to perform annealing for 10 hours or more in the heating temperature of 1000 degreeC - 1400 degreeC in nitrogen-containing atmosphere in the said sintered compact. The heating in a nitrogen-containing atmosphere is for the purpose of reducing the bulk resistivity of the sintered body by reduction of _{SnO 2 .} Examples of the nitrogen-containing atmosphere include a nitrogen atmosphere and an air atmosphere. The heating temperature in the annealing step is preferably 1000°C or higher, more preferably 1100°C or higher, and still more preferably 1200°C or higher, at which the reaction rate of decomposition is sufficiently fast. Further, the heating temperature in the annealing step is preferably 1400°C or less at which a Ga-Sn-O composite oxide is not generated, and more preferably 1300°C or less. Annealing at a heating temperature of 1000°C to 1400°C for 10 hours or longer is because the decomposition reaction proceeds sufficiently. 15 hours or more are preferable and, as for the said heating time, 20 hours or more are more preferable.

As the heating temperature in the sintering step is lowered to the heating temperature in the annealing step, it is preferable in terms of production efficiency to continuously perform the sintering step and the annealing step. However, after the sintering step, after cooling to room temperature, the sintered body may be heated again to the annealing temperature.

The oxide sintered compact obtained by the said process can be finished into a sputtering target member by processing into a desired shape with processing machines, such as a plane grinder, a cylindrical grinder, and a machining machine, as needed. A sputtering target member may be used independently, and it can bond and use it suitably to a backing plate. As a bonding method with a backing plate, the method of bonding an indium type alloy etc. to a copper backing plate as a bonding metal is mentioned, for example.

(6. Film formation method)

According to one Embodiment of this invention, the film-forming method including sputtering a sputtering target member is provided. Although the sputtering method is not limited, RF magnetron sputtering method, DC magnetron sputtering method, AC magnetron sputtering method, pulsed DC magnetron sputtering method, etc. can be preferably used. In one Embodiment of the sputtering target member which concerns on this invention, it is a point with a volume resistivity low, and it is especially preferable for the DC magnetron sputtering method and the pulsed DC magnetron sputtering method.

[Example]

Hereinafter, examples are shown for easy understanding of the present invention and its advantages, but the present invention is not limited to the examples.

Although various measurements and evaluations are required in the Examples and Comparative Examples shown below, the conditions are shown below.

(medium diameter)

The median diameter of various powders is the median by volume when the cumulative distribution of the particle size is measured using a laser diffraction scattering method particle size measuring apparatus (Microtrac MT3000, manufactured by Nikkiso Co., Ltd.) after ultrasonic dispersion for 1 minute using ethanol as a dispersion medium. The diameter (D50) is shown.

(volume resistivity)

The volume resistivity of a sputtering target member is measured by the method mentioned above using the resistivity measuring instrument (The NPS Corporation make, model FELL-TC-100-SB-Sigma 5+, measurement jig RG-5) using the DC 4 probe method.

(relative density)

The measured density of the sputtering target member used as a measurement object is calculated|required by the Archimedes method, and a relative density is calculated|required by relative density = measured density/theoretical density.

(XRD measurement)

The XRD measurement was performed according to the measurement conditions described above using a fully automatic multi-purpose X-ray diffractometer (model: Ultima) manufactured by _{Rigaku Co., Ltd., and I sn} /I and I GaSn /I were calculated from the obtained XRD chart.

(Comparative Example 1)

As raw material powder, Ga ₂ O ₃ powder (median diameter 2.60 µm) and SnO ₂ powder (median diameter: 1.25 µm) were prepared. Ga ₂ O _3: was slurried in the Ga ₂ O ₃ powder and the SnO ₂ powder in a molar ratio of 1 input to the water: SnO ₂ = 1. This slurry was pulverized and mixed using a bead mill. The slurry after pulverization and mixing was dried at 120° C. x 20 hours with a hot air dryer, sieved through a sieve having a sieve size of 250 μm, and separated to recover the mixed powder under the sieve. The median diameter of the mixed powder was 0.84 µm. Next, 1000 g of the obtained mixed powder was filled in a die having a diameter of 210 mm, ^{and pressed with a surface pressure of 400 to 1000 kgf/cm 2} to obtain a disk-shaped molded body. This molded object was heated to the temperature of 1600 degreeC in oxygen atmosphere, and it hold|maintained for 10 hours, and obtained the sintered compact (sputtering target member).

(Comparative Example 2)

The molded object produced on the conditions similar to the comparative example 1 was heated to the temperature of 1550 degreeC in oxygen atmosphere, and it hold|maintained for 10 hours, and the sintered compact (sputtering target member) was obtained.

(Comparative Example 3)

The molded object produced on the conditions similar to the comparative example 1 was heated to the temperature of 1600 degreeC in air atmosphere, and it hold|maintained for 10 hours, and the sintered compact (sputtering target member) was obtained.

(Example 1)

A molded article produced under the same conditions as in Comparative Example 1 was heated to a temperature of 1600° C. in an oxygen atmosphere, and held for 10 hours. Then, the temperature was lowered|hung to 1000 degreeC, and it hold|maintained in air atmosphere for 20 hours, and obtained the sintered compact (sputtering target member).

(Example 2)

A molded article produced under the same conditions as in Comparative Example 1 was heated to a temperature of 1600° C. in an oxygen atmosphere, and held for 10 hours. Then, the temperature was lowered|hung to 1200 degreeC, and it hold|maintained in air atmosphere for 20 hours, and obtained the sintered compact (sputtering target member).

(Example 3)

A mixed powder was produced under the same conditions as in Example 1 except that _{Ga 2} O ₃ powder and SnO ₂ powder were _{mixed so as to have a molar ratio of Ga 2} O ₃ :SnO _{2 =20:80.} The median diameter of the mixed powder was 0.92 µm. Then, the molding and sintering were performed under the same heating conditions as in Example 1 to obtain a sintered body (sputtering target member).

[Table 1]

<Consideration>

Although Comparative Examples 1 to 3 and Examples 1 and 2 had the same raw material composition, I _Sn /I was large, so it can be understood that the volume resistivity of Examples 1 and 2 was remarkably reduced. Further, from the results of Example 3, it is also understood that the volume resistivity is further reduced by lowering the molar ratio of Ga.

Claims (8)

It contains Ga, Sn and O, the remainder is composed of unavoidable impurities, the atomic ratio of Ga and Sn satisfies 0.4≤Ga/(Ga+Sn)≤0.75, and the total peak area (I) in powder X-ray diffraction measurement The sputtering target member whose ratio (I _Sn /I) of the peak area (I _Sn ) of the SnO ₂ phase with respect to 0.02 or more. It contains Ga, Sn and O, the balance is composed of unavoidable impurities, the atomic ratio of Ga and Sn satisfies 0.33≤Ga/(Ga+Sn)≤0.75, and the total peak area (I) in powder X-ray diffraction measurement A sputtering target member, wherein the ratio (I _Sn /I) of the peak area (I _{Sn ) to the SnO 2} phase is 0.02 or more, and the volume resistivity is 0.082 to 13.2 Ω·cm. 3. The method of claim 1 or 2,
Powder X-ray peak area on SnO ₂ for the entire peak area (I) of the diffraction measurement (I _Sn) ratio (I _Sn / I) is 0.1 or more, a sputtering target member. 3. The method of claim 1 or 2,
The sputtering target member whose ratio (I _GaSn /I) of the peak area (I _{GaSn ) of Ga 4} SnO ₈ phase with respect to the total peak area (I) in powder X-ray-diffraction measurement is 0.3 or less. 5. The method of claim 4,
Powder X ratio (I _GaSn / I) is 0.25 or less of a sputtering target member Ga ₄ SnO ₈ peak area (I _GaSn) on to the total peak area (I) in-ray diffraction measurement. According to claim 1,
The sputtering target member whose volume resistivity is 50,000 ohm*cm or less. 3. The method of claim 1 or 2,
A sputtering target member whose relative density is 94% or more. A film-forming method including sputtering the sputtering target member according to claim 1 or 2 .