JP2022044768A - Sputtering target - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sputtering target which allows suppression of contamination of a fluorine element being an impurity in the sputtering target, suppression of generation of an abnormal discharge due to fluorine when a thin film is formed by using the sputtering target, and formation of a thin film having a good orientation.

SOLUTION: A sputtering target includes aluminum, and one or both of a rare earth element and a titanium group element. The content of fluorine is 100 ppm or less.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present disclosure relates to a suitable sputtering target for forming a metal film or a nitride film having good piezoelectric response in a piezoelectric element.

Since it is predicted that the working population will decrease as the birthrate declines and the population ages in modern and future societies, automation using the Internet of Things (IoT) is also being undertaken in the manufacturing industry. In addition, the automobile industry is also shifting to a society in which AI and the like play a central role in manufacturing automobiles that can be automatically driven without human operation.

An important technology in automation and automated driving is wireless ultra-high-speed communication, and high-frequency filters are indispensable for wireless ultra-high-speed communication. Further, in order to speed up wireless communication, the frequency used in the conventional 4th generation mobile communication (4G) is 3.4GHz, and the frequency used in the 5th generation mobile communication (5G) is 3.7GHz. It is planned to shift to the high frequency side to the 5 GHz and 28 GHz bands. When this transition is performed, the high frequency filter also becomes technically difficult with the conventional surface acoustic wave (SAW) filter. Therefore, the technology is changing from elastic surface wave filters to bulk acoustic wave (BAW: Bulk Acoustic Wave) filters.

An aluminum nitride film is mainly used as a piezoelectric film for a BAW filter or a piezoelectric element sensor. Aluminum nitride is used as a piezoelectric film because it is known to have a high amplitude increase coefficient called a Q value (Quality factor). However, since it cannot be used at high temperatures, a nitride film containing an aluminum element and a rare earth element is promising in order to increase the temperature and Q value of the piezoelectric element.

As a sputtering target for forming a nitride film containing an aluminum element and a rare earth element, it is a sputtering target composed of an alloy of Al and Sc and containing Sc at 25 atomic% to 50 atomic%, and has an oxygen content of 25 atomic% to 50 atomic%. There is a disclosure of a sputtering target having a Vickers hardness (Hv) variation of 20% or less and 2000 mass ppm or less (see, for example, Patent Document 1). It is stated that this sputtering target is manufactured by undergoing a melting step and further subjected to plastic working such as a forging step (see, for example, Patent Document 1). Further, Patent Document 1 describes that the variation in the Sc content between the TOP (upper surface of the target) and the BTM (lower surface of the target) of the sputtering target was within ± 2 atomic% (paragraph 0040 of the specification). -0041).

Further, in the method for manufacturing a sputtering target made of an alloy of aluminum and a rare earth element, the element ratio of aluminum and the rare earth element is within the range in which the obtained alloy target is composed of only two kinds of intermetallic compounds. A raw material is prepared, an alloy powder of aluminum and a rare earth element is prepared from this raw material by an atomizing method, and the obtained alloy powder is sintered by a hot press method or a discharge plasma sintering method to be an alloy target in a vacuum atmosphere. There is a technique for producing a body (see, for example, Patent Document 2).

Further, it is known that in the Sc _x Al _1-x N alloy, the piezoelectric constant d ₃₃ changes drastically depending on the composition deviation of the Sc concentration (see, for example, Non-Patent Document 1 and FIG. 3).

WO2017 / 213185 Japanese Unexamined Patent Publication No. 2015-96647

Kazuhiko Kano et al., Denso Technical Review Vol. 17, 2012, p202-207

In the production of aluminum alloys, the melting point of aluminum is as low as 660 ° C, whereas the melting point of the element added to aluminum is 1541 ° C for scandium, 1522 ° C for yttrium, 1668 ° C for titanium, and 1668 ° C for zirconium. Is a very high temperature of 1855 ° C. and 2233 ° C. in the case of hafnium, and the difference in melting point between aluminum and the element to be added is 800 ° C. or more, so that there is almost no range in which aluminum and the element to be added are completely dissolved.

Therefore, as in Patent Document 1, when the amount of scandium added to aluminum is increased, the melting point becomes 1400 ° C. or higher, and the temperature unevenness during solidification after dissolution causes a difference in the growth of the intermetallic compound. Therefore, it is difficult to produce a sputtering target having a uniform composition in the in-plane direction and the thickness direction of the sputtering target.

Further, if it is composed of only intermetallic compounds by using a melting method as in Patent Document 1, it becomes a very hard and brittle sputtering target, and even if an ingot is formed by melting, it is sputtered when plastic working such as forging is performed. The target is prone to cracking.

Further, when produced by the dissolution method as in Patent Document 1, the precipitated phase grows significantly and composition unevenness occurs in the in-plane direction and the thickness direction of the sputtering target. Therefore, even if a thin film is formed by sputtering, it can be obtained. The composition distribution of the alloy thin film becomes unstable.

Patent Document 1 describes that the variation in Sc content between TOP and BTM of the sputtering target was within the range of ± 2 atomic%, but in order to obtain the homogeneity of the formed film. It is also necessary to suppress variations not only in the thickness direction but also in the in-plane direction.

In particular, as pointed out in FIG. 3 of Non-Patent Document 1, it is important to maintain a uniform composition in the in-plane direction and the thickness direction because the characteristics may be extremely changed due to the composition deviation. ..

In order to solve the problem when manufactured by the melting method, it is necessary to eliminate the compositional deviation between aluminum and rare earths at the time of powder as in Patent Document 2, and when sintering, it is close to the final shape of the product. It is conceivable to reduce plastic working by finishing with a shape. However, if impurities such as fluorine, chlorine, and oxygen are mixed too much, fluorine, chlorine, and oxygen in the sputtering target will be released by heating during film formation, and abnormal discharge is likely to occur, and the orientation of the obtained film. It deteriorates the properties and generates particles to reduce the yield of the film.

Therefore, an object of the present disclosure is a sputtering target that suppresses the mixing of fluorine element, which is an impurity, in the sputtering target, and suppresses the generation of abnormal discharge due to fluorine when a thin film is formed using the sputtering target, and orients the sputtering target. It is to provide a sputtering target capable of forming a thin film having good properties.

As a result of diligent studies to solve the above problems, the present inventors have found that the problem of fluorine element contamination can be suppressed by setting the concentration of the fluorine element as an impurity in the sputtering target to a predetermined value or less, and the present invention has been made. Was completed. That is, the sputtering target according to the present invention is a sputtering target containing aluminum and further containing one or both of a rare earth element and a titanium group element, and is characterized by having a fluorine content of 100 ppm or less. do. When a thin film is formed using a sputtering target, it is possible to suppress the occurrence of abnormal discharge due to fluorine and form a thin film with better orientation. Further, by suppressing the generation of abnormal discharge due to fluorine, it is possible to form a thin film with good yield while suppressing the generation of particles.

In the sputtering target according to the present invention, the chlorine content is preferably 100 ppm or less. When a thin film is formed using a sputtering target, it is possible to suppress the occurrence of abnormal discharge due to chlorine and form a thin film with better orientation. Further, by suppressing the generation of abnormal discharge due to chlorine, it is possible to form a thin film with good yield while suppressing the generation of particles.

In the sputtering target according to the present invention, the oxygen content is preferably 500 ppm or less. When a thin film is formed using the sputtering target, it is possible to suppress the occurrence of abnormal discharge due to oxygen and form a thin film having better orientation. Further, by suppressing the generation of abnormal discharge due to oxygen, it is possible to form a thin film with good yield while suppressing the generation of particles.

In the sputtering target according to the present invention, it is preferable that the sputtering target contains an intermetallic compound composed of at least two kinds of elements selected from aluminum, rare earth elements and titanium group elements. Variations in composition can be suppressed by reducing the locations of elemental aluminum, elemental rare earth elements, and elemental titanium group elements. When an intermetallic compound is present in the target, the difference in sputter rate between the metal elements is alleviated, and the composition unevenness of the obtained film is reduced.

In the sputtering target according to the present invention, the intermetallic compound may be present in one, two, three or four types in the sputtering target. Variations in composition can be suppressed by reducing the locations of elemental aluminum, elemental rare earth elements, and elemental titanium group elements. When one or more kinds of intermetallic compounds are present, the difference in sputter rate between metal elements is further alleviated, and the composition unevenness of the obtained film is further reduced.

In the sputtering target according to the present invention, one or more kinds of nitrides of at least one element selected from aluminum, rare earth elements and titanium group elements may be present in the sputtering target. When the nitride film of the piezoelectric element is formed, the temperature of the piezoelectric element can be increased and the Q value can be increased.

In the sputtering target according to the present invention, the rare earth element is preferably at least one of scandium and yttrium. When the nitride film of the piezoelectric element is formed, the temperature of the piezoelectric element can be increased and the Q value can be increased.

In the sputtering target according to the present invention, the titanium group element is preferably at least one of titanium, zirconium and hafnium. When the nitride film of the piezoelectric element is formed, the temperature of the piezoelectric element can be increased and the Q value can be increased.

The sputtering target according to the present invention is at least one of a material containing aluminum and a rare earth element, a material containing aluminum and a titanium group element, and a material containing aluminum, a rare earth element and a titanium group element in the aluminum matrix. Either having a structure in which the species is present, or a phase in which the aluminum matrix contains at least rare earth elements and unavoidable impurities as metal species and a phase containing only titanium group elements and unavoidable impurities as metal species. It is preferable to have a structure composed of a composite phase containing one or both. It is possible to provide a sputtering target having improved conductivity, for example, a sputtering target having improved productivity when forming a film using a DC sputtering apparatus.

The sputtering target of the present disclosure suppresses the mixing of fluorine element, which is an impurity, in the sputtering target, suppresses the generation of abnormal discharge due to fluorine when a thin film is formed using the sputtering target, and has good orientation. A thin film can be formed. Further, by suppressing the generation of abnormal discharge due to fluorine, it is possible to form a thin film with good yield while suppressing the generation of particles.

It is a schematic diagram which shows the measurement point of the composition analysis in the sputter plane inward direction of a disk-shaped target. It is a schematic diagram which shows the measurement point of the composition analysis in the target thickness direction of the disk-shaped target shown in the BB cross section. It is a schematic diagram which shows the measurement point of the composition analysis in the direction in the sputter plane of a square plate-shaped target. FIG. 3 is a schematic view showing measurement points of composition analysis in the target thickness direction of a square plate-shaped target shown in a CC cross section. It is a conceptual diagram for demonstrating the measurement point of the composition analysis of a cylindrical target. It is explanatory drawing for demonstrating the concept of an aluminum matrix. It is an image when the surface of the Al—Sc target in Example 1 was observed with an electron microscope. It is an image when the surface of the Al—Sc target in Comparative Example 4 was observed with an electron microscope. It is an image when the surface of the Al-ScN target in Example 4 was observed with a microscope.

Hereinafter, the present invention will be described in detail by showing embodiments, but the present invention is not construed as being limited to these descriptions. The embodiments may be modified in various ways as long as the effects of the present invention are exhibited.

The sputtering target according to the present embodiment is a sputtering target containing aluminum and further containing one or both of a rare earth element and a titanium group element, and has a fluorine content of 100 ppm or less and 50 ppm or less. It is preferably 30 ppm or less, and more preferably 30 ppm or less. If the fluorine content exceeds 100 ppm, the fluorine in the sputtering target is released by heating during film formation, and the voltage applied to the sputtering target is not stable, causing abnormal discharge and generating particles. The content of fluorine in the sputtering target must be 100 ppm or less because it causes a decrease in the yield of the formed thin film and the formation of a thin film having poor orientation.

In the sputtering target according to the present embodiment, the chlorine content is preferably 100 ppm or less, more preferably 50 ppm or less, still more preferably 30 ppm or less. If the chlorine content exceeds 100 ppm, chlorine in the sputtering target is released by heating during film formation, and the voltage applied to the sputtering target is not stable, causing abnormal discharge and generation of particles. It is preferable to adjust the chlorine content in the sputtering target to 100 ppm or less because it causes a decrease in the yield of the formed thin film and the formation of a thin film having poor orientation.

In the sputtering target according to the present embodiment, the oxygen content is preferably 500 ppm or less, more preferably 300 ppm or less, still more preferably 100 ppm or less. If the oxygen content exceeds 500 ppm, the oxygen in the sputtering target is released by heating during film formation, and the voltage applied to the sputtering target is not stable, causing abnormal discharge and generating particles. It is preferable to adjust the oxygen content in the sputtering target to 500 ppm or less because it causes a decrease in the yield of the formed thin film and the formation of a thin film having poor orientation.

In the sputtering target according to the present embodiment, the carbon content is preferably 200 ppm or less, more preferably 100 ppm or less, still more preferably 50 ppm or less. If the carbon content exceeds 200 ppm, carbon is incorporated into the film during sputtering, and a thin film having deteriorated crystallinity is formed. Further, when a strong compound is formed on the surface of the target, particles are generated due to abnormal discharge that impairs conductivity, and the yield of the film is lowered. Therefore, it is preferable to adjust the carbon content in the sputtering target to 200 ppm or less.

In the sputtering target according to the present embodiment, the silicon content is preferably 200 ppm or less, more preferably 100 ppm or less, still more preferably 50 ppm or less. When the silicon content exceeds 200 ppm, silicon oxides and nitrides are formed during sputtering, which causes abnormal discharge, generates particles, and the yield of the formed thin film decreases. Therefore, the sputtering target. It is preferable to adjust the content of silicon in the mixture to 200 ppm or less.

In the sputtering target according to the present embodiment, the composition of the sputtering target in the sputter plane inward direction and the target thickness direction in (Condition 1) or (Condition 2) has a difference of ± 3% from the reference composition. It is within ± 2%, more preferably ± 1% or less. Here, the reference composition is an average value of the total composition of 18 points measured according to (Condition 1) or (Condition 2). If the difference exceeds ± 3% with respect to the reference composition, the sputtering rate may differ when the sputtering target is formed, and when the piezoelectric film of the piezoelectric element is formed, the piezoelectric characteristics of the piezoelectric film are applied to each substrate. In addition, even if the same substrate is used, the piezoelectric characteristics may differ due to the difference in composition depending on the location of the piezoelectric film. Therefore, in order to suppress the deterioration of the yield of the piezoelectric element, it is preferable to control the difference between the composition in the sputtering surface inward direction and the target thickness direction of the sputtering target within ± 3% with respect to the reference composition. If the composition is uniform in the in-plane direction and the thickness direction, it is possible to suppress a decrease in yield due to a change in characteristics such as piezoelectric responsiveness due to composition deviation when a thin film used for a piezoelectric element or the like is formed. ..

(Condition 1)
Inward direction of sputtering plane: The sputtering target is a disk-shaped target having a center O and a radius r, and the measurement point of composition analysis is on a virtual cross line orthogonal to the center O as an intersection, and the measurement point is 1 of the center O. There are a total of 9 locations, 4 locations in total, 0.45r away from the center O, and 4 locations in total, 0.9r away from the center O.
Target thickness direction: A cross section is formed through any one of the virtual cross lines, and the cross section is a rectangle having a vertical t (that is, a target thickness of t) and a horizontal 2r, and is used for composition analysis. The measurement points are a total of three points (referred to as points a, X, and b) 0.45 t above and below the center X and the center X on the vertical cross section passing through the center O, and are on the cross section from the point a. A total of 2 locations 0.9r away from the left and right sides, a total of 2 locations 0.9r away from point X toward the left and right sides, and 0.9r from point b toward the left and right sides. A total of 9 points, 2 points apart from each other, are used as measurement points.
(Condition 2)
Inward direction of sputtering surface: The sputtering target includes a rectangle having a vertical length of L1 and a horizontal length of L2 (provided that a square in which L1 and L2 are equal to each other is included, or the rectangle has a length J. Includes a rectangle with the sides of a cylindrical shape of circumference K expanded, in which L2 corresponds to length J, L1 corresponds to circumference K, and length J and circumference K correspond to J> K. , J = K or J <K), and the measurement point of the composition analysis is a virtual cross line orthogonal to the intersection of the center of gravity O, and the virtual cross line is orthogonal to the side of the rectangle. At this time, one place of the center of gravity O, a total of two places on the virtual cross line separated from the center of gravity O in the vertical direction by 0.25L1, and a total of two places separated from the center of gravity O in the horizontal direction by 0.25L2. , A total of 2 locations separated from the center of gravity O in the vertical direction by 0.45 L1 and a total of 2 locations separated by a distance of 0.45 L2 in the horizontal direction from the center of gravity O, for a total of 9 locations.
Target thickness direction: Of the virtual cross lines, a cross section is formed that passes through a line parallel to either one of the vertical L1 and the horizontal L2, and when one side is the horizontal L2, the cross section is the vertical t (that is, the above-mentioned). The target thickness is t), it is a rectangle with a horizontal L2, and the measurement points for composition analysis are the center X on the vertical crossing line passing through the center of gravity O and a total of three points (a) 0.45 t above and below the center X. Point, point X, point b), a total of two points on the cross section that are 0.45 L2 away from point a toward the left and right sides, and 0.45 L2 away from point X toward the left and right sides. A total of 9 points, a total of 2 points and a total of 2 points separated from point b by 0.45 L2 toward the left and right sides, are set as measurement points.

FIG. 1 is a schematic view showing measurement points (hereinafter, abbreviated as measurement points) for composition analysis in the direction in the sputtered surface of the disk-shaped target, and is referred to with reference to FIG. 1 (condition 1). The measurement points in the sputter plane inward direction of the sputtering target will be described. In the case of a disk-shaped target, the radius is preferably 25 to 225 mm, more preferably 50 to 200 mm. The thickness of the target is preferably 1 to 30 mm, more preferably 3 to 26 mm. In this embodiment, more effect can be expected for a large target.

In FIG. 1, the sputtering target 200 is a disk-shaped target having a center O and a radius r. The measurement points are on a virtual crosshair (L) orthogonal to the center O as an intersection, and one point (S1) of the center O and a total of four points (S3, S5, S6 and S8) 0.45 r away from the center O. ) And a total of 4 locations (S2, S4, S7 and S9) 0.9r away from the center O, for a total of 9 locations.

FIG. 2 is a schematic view showing measurement points of composition analysis in the target thickness direction of the disc-shaped target shown in the BB cross section of FIG. 1, and is a schematic view of the sputtering target of (Condition 1) with reference to FIG. The measurement points in the target thickness direction will be described.

In FIG. 2, the BB cross section of FIG. 1 is a rectangle having a length t (that is, a target thickness t) and a width 2r. Then, the measurement points are the center X (C1) on the vertical crossing line passing through the center O and a total of three points (point a (C4), point X (C1), and point b (C5) separated from the center X by 0.45 tons up and down. ), A total of two locations (C6, C7) 0.9r away from point a toward the left and right sides on the cross section, and 0.9r away from point X toward the left and right sides. A total of 9 points (C2, C3) and a total of 2 points (C8, C9) 0.9r away from point b toward the left and right sides are used as measurement points.

FIG. 3 is a schematic view showing measurement points of composition analysis in the sputtered surface inward direction of the square plate-shaped target, and the measurement points in the sputtered surface inward direction of the sputtering target of (Condition 2) will be described with reference to FIG. do. In the case of a rectangular or square target, the vertical length and the horizontal length are preferably 50 to 450 mm, more preferably 100 to 400 mm. The thickness of the target is preferably 1 to 30 mm, more preferably 3 to 26 mm. In this embodiment, more effect can be expected for a large target.

The sputtering target 300 is a rectangular target having a vertical length of L1 and a horizontal length of L2 (including a square in which L1 and L2 are equal to each other). In FIG. 3, the sputtering target 300 is L1 =. The form which is L2 is shown. The measurement point is a virtual cross line (Q) orthogonal to the center of gravity O as an intersection, and when the virtual cross line is orthogonal to the side of a rectangle (or a square), one point (P1) of the center of gravity O is on the virtual cross line. There are a total of 2 locations (P6, P8) separated from the center of gravity O in the vertical direction by 0.25L1, a total of 2 locations (P3, P5) separated by a distance of 0.25L2 in the horizontal direction from the center of gravity O, and the center of gravity O. A total of 2 locations (P7, P9) separated from the center of gravity 0.45L1 in the vertical direction, and a total of 2 locations (P2, P4) separated from the center of gravity O in the horizontal direction by 0.45L2. It is a place. When the sputtering target is rectangular, L1 and L2 can be appropriately selected regardless of the length of the side.

FIG. 4 is a schematic view showing measurement points of composition analysis in the target thickness direction of the square plate-shaped target shown in the CC cross section of FIG. 3, and the sputtering target of (Condition 2) with reference to FIG. The measurement points in the target thickness direction of the above will be described.

In FIG. 4, the CC cross section of FIG. 3 forms a cross section that passes through a line parallel to the horizontal side, and the cross section is a rectangle with a vertical t (that is, the thickness of the target is t) and a horizontal L2, and is measured. A total of three locations (referred to as points a (D4), X (D1), and b (D5)), 0.45 tons above and below the center X and the center X on the vertical cross-sectional line passing through the center of gravity O, said. A total of 2 locations (D6, D7) 0.45L2 away from point a toward the left and right sides on the cross section, and a total of 2 locations (D2, D7) 0.45L2 away from point X toward the left and right sides. A total of 9 points (D3) and 2 points (D8, D9) separated from the point b toward the left and right sides by 0.45 L2 are used as measurement points.

(Cylindrical sputtering target)
FIG. 5 is a conceptual diagram for explaining a measurement point of a cylindrical target. When the sputtering target has a cylindrical shape, the side surface of the cylinder is the sputtering surface, and the developed view is rectangular or square. Therefore, (Condition 2) can be considered in the same manner as in FIGS. 3 and 4. In FIG. 5, when the sputtering target 400 has a cylindrical shape with a height (length) J and a body circumference of K, the EE cross section and the DD development surface so that the cross sections are at both ends are considered. .. First, the measurement points of the composition analysis in the target thickness direction are considered in the EE cross section in the same manner as in FIG. That is, it is considered that the height J of the cylindrical material corresponds to L2 in FIG. 4 and the thickness of the cylindrical material corresponds to the thickness t in FIG. 4, and the measurement point is set. Further, the measurement points in the inward direction of the spatter surface are considered in the same manner as in FIG. 3 on the DD development surface. That is, it is considered that the height J of the cylindrical material corresponds to L2 in FIG. 3 and the peripheral length K of the body of the cylindrical material corresponds to L1 in FIG. The relationship of J> K, J = K or J <K is established between the length J and the perimeter K. In the case of a cylindrical target, the length of the waist circumference of the cylinder is preferably 100 to 350 mm, more preferably 150 to 300 mm. The length of the cylinder is preferably 300 to 3000 mm, more preferably 500 to 2000 mm. The thickness of the target is preferably 1 to 30 mm, more preferably 3 to 26 mm. In this embodiment, more effect can be expected for a large target.

The sputtering target according to the present embodiment is at least one of a material containing aluminum and a rare earth element, a material containing aluminum and a titanium group element, and a material containing aluminum, a rare earth element, and a titanium group element in the aluminum matrix. A phase having a structure in which one species is present, or a phase containing at least rare earth elements and unavoidable impurities as metal species, a phase containing only titanium group elements and unavoidable impurities as metal species, and a phase in which the aluminum matrix contains at least rare earth elements and unavoidable impurities. It is preferable to have a structure composed of a composite phase containing only one of rare earth elements, titanium group elements and unavoidable impurities as the metal species. It is an object of the present invention to provide a sputtering target having improved conductivity, for example, a sputtering target having improved productivity when forming a film by using a DC sputtering apparatus.

Next, the specific microstructure of the sputtering target will be described with respect to this embodiment. The specific microstructure of the sputtering target is classified into, for example, the first structure to the fifth structure and their variants. Here, the morphology having the aluminum matrix is a second structure, a fifth structure, and a modification thereof, and in particular, a second structure and a second structure-2, which is a modification thereof, and a modification thereof. , The fifth organization and its variant, the fifth organization-2.

[First organization]
The sputtering target according to the present embodiment is a material containing aluminum and a rare earth element (hereinafter, also referred to as RE), a material containing aluminum and a titanium group element (hereinafter, also referred to as TI), and aluminum and a rare earth element. It has a first structure composed of at least one of materials containing a titanium group element and a titanium group element. That is, in the first structure, the form in which the material A containing Al and RE, the material B containing Al and TI, or the material C containing Al, RE and TI is present, and the coexistence of the material A and the material B, the material. There are seven material combinations: coexistence of A and material C, coexistence of material B and material C, or coexistence of material A, material B and material C.

In the present embodiment, the term "material" means a material constituting a sputtering target, and includes, for example, an alloy or a nitride. Further, alloys include, for example, solid solutions, eutectics, and intermetallic compounds. If the nitride is metal-like, it may be included in the alloy.

[Second organization]
The sputtering target according to the present embodiment is at least one of a material containing aluminum and a rare earth element, a material containing aluminum and a titanium group element, and a material containing aluminum, a rare earth element, and a titanium group element in the aluminum matrix. It has a second tissue in which one species is present. That is, in the second structure, there are seven combinations of materials mentioned in the first structure in the aluminum matrix. That is, in the second structure, the form in which the material A, the material B or the material C is present in the aluminum matrix, the coexistence of the material A and the material B in the aluminum matrix, and the coexistence of the material A and the material C. There is a combination of forms in which coexistence, coexistence of material B and material C, or coexistence of material A, material B, and material C is observed.

In the present embodiment, the term "aluminum matrix" can also be referred to as an aluminum matrix. In FIG. 6, the concept of the aluminum matrix is described by taking the second structure as an example. In the sputtering target 100, the fine structure thereof is a material containing aluminum and a rare earth element in the aluminum matrix, specifically, an Al—RE alloy is present. That is, the Al matrix 3 connects the plurality of Al—RE alloy particles 1 together. The Al—RE alloy particle 1 is an aggregate of crystal grains 2 of the Al—RE alloy. The boundary between the crystal grains 2a of the Al—RE alloy and the crystal grains 2b of the adjacent Al—RE alloy is a grain boundary. The Al matrix 3 is an aggregate of aluminum crystal grains 4. The boundary between the aluminum crystal grains 4a and the adjacent aluminum crystal grains 4b is a grain boundary. As described above, in the present embodiment, the term "mother phase" means a phase in which a plurality of metal particles, alloy particles, or nitride particles are joined together, and the joined phase itself is also an aggregate of crystal grains. It's a concept. In general, intermetallic compounds or nitrides are characterized by poor electrical conductivity and plastic workability (ductility), which are the characteristics of metals. When the Al-RE alloy of the sputtering target is composed of only the intermetallic compound or only the nitride or the intermetallic compound and the nitride, the electrical conductivity of the sputtering target tends to decrease. However, the presence of the aluminum (matrix) phase can prevent the electrical conductivity of the sputtering target as a whole from deteriorating. Further, when the Al-RE alloy of the sputtering target is composed of only the intermetallic compound or only the nitride or the intermetallic compound and the nitride, the sputtering target tends to be very brittle. However, the presence of the aluminum (matrix) phase can alleviate the brittleness of the target.

[Third organization]
The sputtering target according to the present embodiment is either a phase containing only aluminum and unavoidable impurities as a metal species, a phase containing only rare earth elements and unavoidable impurities as a metal species, and a phase containing only titanium group elements and unavoidable impurities as metal species. It has a third structure composed of a composite phase containing one or both. That is, the third structure is a form composed of a composite phase containing a phase containing aluminum as a metal species and a phase containing a rare earth element as a metal species, a phase containing aluminum as a metal species, and a titanium group as a metal species. A form composed of a composite phase containing an element-containing phase, or a composite phase including a phase containing aluminum as a metal species, a phase containing a rare earth element as a metal species, and a phase containing a titanium group element as a metal species. There are three combinations of the forms that have been made.

Examples of the unavoidable impurities include Fe and Ni, and the atomic% concentration of the unavoidable impurities is, for example, preferably 200 ppm or less, more preferably 100 ppm or less.

In the present embodiment, the term "phase" is a concept of an aggregate of particles having the same composition, for example, an aggregate of particles having the same composition on a solid phase.

In the present embodiment, the term "composite phase" is a concept that two or more kinds of "phases" exist. These phases differ in composition from type to type.

[Fourth organization]
The sputtering target according to the present embodiment includes a phase containing aluminum and further containing one or both of a rare earth element and a titanium group element, a phase containing only aluminum as a metal species and unavoidable impurities, and a rare earth element as a metal species. It has a fourth structure composed of a phase containing only unavoidable impurities and at least one phase of a phase containing only a titanium group element and a phase containing only unavoidable impurities as a metal species, and a composite phase containing the same. That is, in the fourth structure, the following 21 combinations of phases exist. Here, the phase containing aluminum and a rare earth element is referred to as phase D, the phase containing aluminum and a titanium group element is referred to as phase E, and the phase containing aluminum, a rare earth element and a titanium group element is referred to as phase F. Further, as a metal species, a phase containing only aluminum and unavoidable impurities is referred to as phase G, as a metal species, a phase containing only rare earth elements and unavoidable impurities is referred to as phase H, and as a metal species, a phase containing only titanium group elements and unavoidable impurities is referred to as phase I. do. The fourth structure consists of the following complex phases: phase D and phase G, phase D and phase H, phase D and phase I, phase D and phase G and phase H, phase D and phase G and phase I, phase. D and phase H and phase I, phase D and phase G and phase H and phase I, phase E and phase G, phase E and phase H, phase E and phase I, phase E and phase G and phase H, phase E and Phase G and Phase I, Phase E and Phase H and Phase I, Phase E and Phase G and Phase H and Phase I, Phase F and Phase G, Phase F and Phase H, Phase F and Phase I, Phase F and Phase G And phase H, phase F and phase G and phase I, phase F and phase H and phase I, or phase F, phase G, phase H and phase I.

[Fifth organization]
The sputtering target according to the present embodiment contains at least one or both of a phase containing only rare earth elements and unavoidable impurities as a metal species and a phase containing only titanium group elements and unavoidable impurities as a metal species in the aluminum matrix. It has a fifth structure composed of complex phases containing. The fifth structure is composed of a composite phase in which the following three phases are present in the aluminum parent phase. That is, in the fifth structure, a composite phase in which the phase H is present in the aluminum matrix, a composite phase in which the phase I is present in the aluminum matrix, or a phase H and the phase I are present in the aluminum matrix. It is composed of a composite phase.

Also in this embodiment, the term "aluminum matrix" can also be referred to as an aluminum matrix. In the fifth structure, in the sputtering target, the microstructure is a composite phase in which phase H, phase I, or both phase H and phase I are present in the aluminum matrix. The aluminum matrix is an aggregate of aluminum crystal grains, and the boundary between the aluminum crystal grains and the adjacent aluminum crystal grains is a grain boundary. Phase H is, for example, the concept of an aggregate of particles having the same composition. The same applies to Phase I. If both phase H and phase I are present, then there are two phases with different compositions in the aluminum matrix.

[Fifth tissue modification example]
The sputtering target according to the present embodiment includes a fifth structure in which the composite phase further contains a phase containing only aluminum and unavoidable impurities as metal species.
The fifth structure is composed of a composite phase in which the following three phases are present in the aluminum parent phase. That is, this composite phase is a composite phase in which phase H and phase G are present in the aluminum matrix, a composite phase in which phase I and phase G are present in the aluminum matrix, or phase H in the aluminum matrix. It is a composite phase in which phase I and phase G exist.

Modifications of the first to fifth tissues and the fifth tissue further include the following forms.

[First Organization-2]
The sputtering target according to the present embodiment has a first structure and the material is an alloy, has a first structure, and the material is a nitride, or has a first structure. And, the form in which the material is a combination of an alloy and a nitride is exemplified. Here, the material is a form in which a material A containing Al and RE, a material B containing Al and TI, or a material C containing Al, RE and TI exists, a coexistence of the material A and the material B, and the material A and the material A. There are seven combinations of materials in the form of coexistence of material C, coexistence of material B and material C, or coexistence of material A, material B and material C.

[Second Organization-2]
The sputtering target according to the present embodiment has a second structure and the material is an alloy, has a second structure, and the material is a nitride, or has a second structure. However, the form in which the material is a combination of an alloy and a nitride is exemplified. Here, the material is a combination of seven materials listed in [First Structure].

[Third Organization-2]
The sputtering target according to the present embodiment has a third structure and the composite phase is a composite of a metal phase, has a third structure, and the composite phase is a composite of a nitride phase. Alternatively, a form having a third structure and the composite phase being a composite of a metal phase and a nitride phase is exemplified. Here, "the composite phase is a composite of a metal phase" includes a composite phase including an Al phase and a RE phase, a composite phase including an Al phase and a TI phase, or a composite phase including an Al phase, a RE phase and a TI phase. Means a composite phase. "The composite phase is a composite of a nitride phase" means a composite phase containing an AlN phase and a REN phase, a composite phase including an AlN phase and a TIN phase, or a composite phase including an AlN phase, a REN phase and a TIN phase. Means phase. Further, "the composite phase is a composite of a metal phase and a nitride phase" means, for example, a composite phase including an Al phase and a REN phase, a composite phase including an AlN phase and a RE phase, and an Al phase and an AlN phase. Complex phase including Al phase and RE phase, Composite phase including Al phase, AlN phase and REN phase, Composite phase including Al phase, RE phase and REN phase, Composite phase including AlN phase, RE phase and REN phase. , Al phase, AlN phase, RE phase and REN phase, composite phase including Al phase and TI phase, composite phase including AlN phase and TI phase, Al phase, AlN phase and TI phase. Complex phase including Al phase, composite phase including Al phase, AlN phase and TI phase, composite phase including Al phase, TI phase and TI phase, composite phase including AlN phase, TI phase and TI phase, Al phase and AlN. A composite phase including a phase, a TI phase and a TIN phase, a composite phase including an Al phase, an AlN phase, a RE phase and a TI phase, a composite phase including an Al phase, an AlN phase, a REN phase and a TI phase, and an Al phase and a composite phase. A composite phase containing an AlN phase, a RE phase and a TIN phase, a composite phase including an Al phase, an AlN phase, a REN phase and a TIN phase, a composite phase including an Al phase, a RE phase, a REN phase and a TI phase, and an AlN phase. A composite phase including RE and RE phase, REN phase and TI phase, a composite phase including Al phase, RE phase, REN phase and TIN phase, a composite phase including AlN phase, RE phase, REN phase and TIN phase, Al. A composite phase containing a phase, a RE phase, a TI phase, and a TI phase, a composite phase including an AlN phase, a RE phase, a TI phase, and a TI phase, and a composite phase including an Al phase, a REN phase, a TI phase, and a TI phase. A composite phase including an AlN phase, a REN phase, a TI phase and a TI phase, a composite phase including an Al phase, an AlN phase, a RE phase, a REN phase and a TI phase, an Al phase, an AlN phase, a RE phase, a REN phase and a TIN. Composite phase including phase, composite phase including Al phase, AlN phase, RE phase, TI phase and TI phase, composite phase including Al phase, AlN phase, REN phase, TI phase and TI phase, Al phase and A composite phase including a RE phase, a REN phase, a TI phase, and a TI phase, a composite phase including an AlN phase, a RE phase, a REN phase, a TI phase, and a TI phase, or an Al phase, an AlN phase, a RE phase, and a REN phase. It means a composite phase including the TI phase and the TI phase. The notation of valence is omitted.

In this embodiment, the term "metal phase" is a concept of a phase consisting of a single metal element.

In this embodiment, the term "nitride phase" is a concept of a phase composed of nitrides.

[Fourth Organization-2]
The sputtering target according to the present embodiment has a fourth structure in which the composite phase is a composite of an alloy phase and a metal phase, and the composite phase has an alloy phase and a nitrided phase. It has a fourth structure, which is a composite of physical phases, and the composite phase is a composite of a nitride phase and a metal phase, has a fourth structure, and the composite phase is different from the nitride phase. Examples thereof are a composite of a nitride phase, or a composite having a fourth structure and the composite phase is a composite of an alloy phase, a metal phase, and a nitride phase. Here, the metal phase is a case where the phase G, the phase H and the phase I are in a metallic state without being nitrided or oxidized, respectively, and the alloy phase is a case where the phase D, the phase E and the phase F are respectively. It is a case where the phase is in the state of an alloy without being nitrided or oxidized, and the nitride phase is a case where the phase G, the phase H, the phase I, the phase D, the phase E and the phase F are each nitrided. be. Further, the metal phase, the alloy phase and the nitride phase may be present in one type or two or more types in the target, respectively, and a plurality of metal phases, alloy phases and nitride phases are present in combination. In some cases. Examples of these forms include, for example, a metal phase of phase G, a metal phase of phase G, a metal phase of phase H, and a nitride of phase H in at least one of the alloy phase of phase D or the nitride phase of phase D. A form including at least one of a physical phase, a metal phase of phase I, and a nitride phase of phase I, a metal phase of phase G, and a metal phase of phase G in at least one phase of an alloy phase of phase E or a nitride phase of phase E. A form comprising at least one of a nitride phase, a metal phase of phase H, a nitride phase of phase H, a metal phase of phase I, and a nitride phase of phase I, an alloy phase of phase F or a nitride phase of phase F. A form in which at least one phase contains at least one of a metal phase of phase G, a nitride phase of phase G, a metal phase of phase H, a nitride phase of phase H, a metal phase of phase I, and a nitride phase of phase I. There is.

In this embodiment, the term "alloy phase" is a concept of a phase composed of an alloy.

[Fifth Organization-2]
The sputtering target according to the present embodiment has a fifth structure, and the composite phase has a fifth structure, which is a composite of an aluminum matrix phase and at least one metal phase. The composite phase is a composite of an aluminum matrix phase and at least one nitride phase among an aluminum nitride phase, a nitride phase of a rare earth element, and a nitride phase of a titanium group element, or has a fifth structure. Moreover, the form in which the composite phase is a composite of a metal phase and a nitride phase is exemplified. Here, "at least one metal phase" means only phase H, only phase I, or both phase H and phase I. "The composite phase is a composite of an aluminum nitride phase and at least one nitride phase among an aluminum nitride phase, a nitride phase of a rare earth element, and a nitride phase of a titanium group element." Complex phase including REN phase, compound phase including Al matrix phase and TIN phase, composite phase including Al matrix phase, AlN phase and REN phase, complex phase including Al matrix phase, AlN phase and TIN phase. , A composite phase containing an Al mother phase, a REN phase and a TIN phase, or a composite phase including an Al mother phase, an AlN phase, a REN phase and a TIN phase. "The composite phase is a composite of a metal phase and a nitride phase" means, for example, a composite phase including an Al matrix phase, a RE phase and a TIN phase, and a composite phase including an Al matrix phase, a REN phase and a TI phase. , Al mother phase, AlN phase, RE phase and TI phase, Al mother phase, AlN phase, REN phase and TI phase, Al mother phase, AlN phase, RE phase and TIN phase. Complex phase including Al matrix phase, RE phase, REN phase and TI phase, Composite phase including Al matrix phase, RE phase, REN phase and TIN phase, Al matrix phase, RE phase and TI phase. A composite phase containing and a TIN phase, a composite phase containing an Al mother phase, a REN phase, a TI phase and a TI phase, a composite phase including an Al mother phase, an AlN phase, a RE phase, a REN phase and a TI phase, and an Al mother. A composite phase including a phase, an AlN phase, a RE phase, a REN phase, and a TIN phase, a composite phase including an Al mother phase, an AlN phase, a RE phase, a TI phase, and a TIN phase, and an Al mother phase, an AlN phase, and a REN phase. A composite phase including a TI phase and a TIN phase, a composite phase including an Al mother phase, a RE phase, a REN phase, a TI phase and a TI phase, or an Al mother phase, an AlN phase, a RE phase, a REN phase and a TI phase. It means a composite phase including a TIN phase. In addition, N means a nitrogen element, for example, "AlN phase" means an aluminum nitride phase. In addition, the notation of the valence of the nitride is omitted.

In the fifth structure-2, a form in which the composite phase is a composite of a nitride phase including an aluminum nitride phase is included. That is, the composite phase in the fifth organization-2 is a composite phase in which the AlN phase is further added in each of the morphological examples listed in the fifth organization. Specifically, among the fifth organization-2, as the present embodiment, in particular,
(1) "The composite phase is a composite of an aluminum nitride phase and at least one of the aluminum nitride phase, the nitride phase of a rare earth element, and the nitride phase of a titanium group element", but the Al matrix phase. When it is a composite phase including an AlN phase and an AlN phase, a composite phase including an Al matrix phase, an AlN phase and a TIN phase, or a composite phase including an Al matrix phase, an AlN phase, a REN phase and a TIN phase. When,
(2) "The composite phase is a composite of a metal phase and a nitride phase" is a composite phase including an Al matrix phase, an AlN phase, a RE phase and a TI phase, and an Al matrix phase, an AlN phase, a REN phase and a TI. A composite phase including a phase, a composite phase including an Al mother phase, an AlN phase, a RE phase, and a TIN phase, a composite phase including an Al mother phase, an AlN phase, a RE phase, a REN phase, and a TI phase, and an Al mother phase. A composite phase containing an AlN phase, a RE phase, a REN phase, and a TIN phase, a composite phase including an Al mother phase, an AlN phase, a RE phase, a TI phase, and a TI phase, an Al mother phase, an AlN phase, a REN phase, and a TI phase. The case where the composite phase includes the Al mother phase, the AlN phase, the RE phase, the REN phase, the TI phase, and the TIN phase is included.

In the sputtering target according to the present embodiment, it is preferable that the sputtering target contains an intermetallic compound composed of at least two kinds of elements selected from aluminum, rare earth elements and titanium group elements. For example, in the first structure or the second structure, such intermetallic compounds are present in the sputtering target. Further, when the alloy phase is present in the fourth structure, the intermetallic compound is present in the alloy phase. Variations in composition can be suppressed by reducing the locations of elemental aluminum, elemental rare earth elements, and elemental titanium group elements. In addition, when the target is composed of a combination of simple substances, the sputter rate for each simple substance is applied at the time of sputtering, and the difference is remarkable, so that it is difficult to obtain a homogeneous film. If is present, the difference in sputter rate between the metal elements is alleviated, and the composition unevenness of the obtained film is reduced.

In the sputtering target according to the present embodiment, the intermetallic compound may be present in one kind, two kinds, three kinds or four kinds in the sputtering target. For example, when an alloy phase is present in the first structure, the second structure or the fourth structure, one, two, three or four kinds depending on the number of kinds of metal species in the sputtering target. Intermetallic compounds are present. When the target is composed of a combination of simple substances, the sputter rate for each simple substance is applied at the time of sputtering, and the difference is remarkable. Therefore, it is difficult to obtain a homogeneous film. When a plurality of types are present, the difference in sputter rate between the metal elements is further alleviated, and the composition unevenness of the obtained film is further reduced.

In the sputtering target according to the present embodiment, one or more kinds of nitrides of at least one element selected from aluminum, rare earth elements and titanium group elements may be present in the sputtering target. When the nitride film of the piezoelectric element is formed, the temperature of the piezoelectric element can be increased and the Q value can be increased. For example, in each of the first structure to the fifth structure, the nitride is present by introducing the nitrogen element. There are 1 type, 2 types, 3 types, 4 types, or more types of nitrides depending on the number of metal types.

In the sputtering target according to the present embodiment, the rare earth element is preferably at least one of scandium and yttrium. When the nitride film of the piezoelectric element is formed, the temperature of the piezoelectric element can be increased and the Q value can be increased. As rare earth elements, there are scandium only, yttrium only, or a combination of scandium and yttrium. When both scandium and yttrium are included as rare earth elements, for example, in the form in which an Al—Sc-Y material or an Al—Sc—Y phase is present, as well as an Al—Sc material, an Al—Y material and an Al—Sc—Y material. There is a form in which at least two kinds of materials are present at the same time, or a form in which at least two kinds of phases of Al—Sc phase, Al—Y phase and Al—Sc—Y phase are present at the same time.

In the sputtering target according to the present embodiment, the titanium group element is preferably at least one of titanium, zirconium and hafnium. When the nitride film of the piezoelectric element is formed, the temperature of the piezoelectric element can be increased and the Q value can be increased. Examples of the titanium group elements include titanium only, zirconium only, hafnium only, titanium and zirconium, titanium and hafnium, zirconium and hafnium, or titanium and zirconium and hafnium. When the titanium group elements include, for example, both titanium and zirconium, for example, in the form in which an Al—Ti—Zr material or an Al—Ti—Zr phase is present, an Al—Ti material, an Al—Zr material and an Al— There is a form in which at least two kinds of Ti—Zr materials are present at the same time, or a form in which at least two kinds of phases of Al—Ti phase, Al—Zr phase and Al—Ti—Zr phase are present at the same time. Further, when both titanium and hafnium are contained, for example, in the form in which an Al—Ti—Hf material or an Al—Ti—Hf phase is present, as well as in an Al—Ti material, an Al—Hf material and an Al—Ti—Hf material. There is a form in which at least two kinds of materials are present at the same time, or a form in which at least two kinds of phases of Al—Ti phase, Al—Hf phase and Al—Ti—Hf phase are present at the same time. Further, when both zirconium and hafnium are contained, for example, in the form in which an Al-Zr-Hf material or an Al-Zr-Hf phase is present, as well as an Al-Zr material, an Al-Hf material and an Al-Zr-Hf material. There is a form in which at least two kinds of materials are present at the same time, or a form in which at least two kinds of phases of Al—Zr phase, Al—Hf phase and Al—Zr—Hf phase are present at the same time. When including titanium, zirconium and hafnium, for example, in the form in which an Al-Ti-Zr-Hf material or an Al-Ti-Zr-Hf phase is present, as well as an Al-Ti material, an Al-Zr material, an Al-Hf material, Al-Ti-Zr material, Al-Ti-Hf material, Al-Zr-Hf material and Al-Ti-Zr-Hf material in which at least two kinds of materials are present at the same time, or Al-Ti phase, Al- A form in which at least two phases of Zr phase, Al—Hf phase, Al—Ti—Zr phase, Al—Ti—Hf phase, Al—Zr—Hf phase and Al—Ti—Zr—Hf phase are present at the same time, and further. In the above-mentioned form, a material or phase containing two of Ti, Zr and Hf in addition to Al is further added, and a material or phase containing one of Ti, Zr and Hf in addition to Al is further added. There is a form.

Examples of the sputtering target according to the present embodiment include scandium and yttrium as rare earth elements contained in aluminum, and titanium, zirconium, hafnium and the like as titanium group elements contained in aluminum. The scandium content in the target is preferably 5 to 75 atomic%. More preferably, it is 10 to 50 atomic%. The content of yttrium in the target is preferably 5 to 75 atomic%. More preferably, it is 10 to 50 atomic%. The titanium content in the target is preferably 5 to 75 atomic%. More preferably, it is 10 to 50 atomic%. The zirconium content in the target is preferably 5 to 75 atomic%. More preferably, it is 10 to 50 atomic%. The hafnium content in the target is preferably 5 to 75 atomic%. More preferably, it is 10 to 50 atomic%. The sputtering target according to the present embodiment contains at least one kind of the sputtering target together with aluminum so that each of the above elements satisfies the above content.

When forming an alloy containing a rare earth element and a titanium group element in aluminum, first, an aluminum-rare earth element alloy such as an aluminum-scandium alloy and an aluminum-ittrium alloy is formed in the above composition range. Next, an alloy of an aluminum-titanium group element such as an aluminum-titanium alloy, an aluminum-zylconyl alloy, and an aluminum-hafnium alloy is formed in the above composition range. Then, the alloy of the aluminum-rare earth element and the alloy of the aluminum-titanium group element are mixed while adjusting the contents thereof to form an aluminum-rare earth element-titanium group element alloy. Further, the alloy of aluminum-rare earth element-titanium group element may be directly formed without mixing the binary alloy as described above to form the ternary alloy. By forming an intermetallic compound in a sputtering target or forming a nitride film during sputtering, a piezoelectric film capable of obtaining a high Q value even at a high temperature can be formed.

A method for manufacturing a sputtering target according to the present embodiment will be described. The method for producing a sputtering target according to the present embodiment is as follows: (1) a raw material composed of aluminum and a rare earth element, (2) a raw material composed of aluminum and a titanium group element, or (3) an aluminum, a rare earth element and a titanium group element. From the first step of producing the raw material, and the raw material manufactured in the first step, (1) alloy powder of aluminum and rare earth element (aluminum-rare earth element), (2) aluminum and titanium group element The second step of producing the alloy powder (aluminum-titanium group element) or (3) the alloy powder of aluminum, the rare earth element and the titanium group element (aluminum-rare earth element-titanium group element), and the second step. Third step of obtaining (1) aluminum-rare earth element sintered body, (2) aluminum-titanium group element sintered body, and (3) aluminum-rare earth element-titanium group element sintered body from the powder obtained in And have. When manufacturing a sputtering target containing an aluminum matrix, the method for manufacturing the sputtering target is mainly as an aluminum raw material to be a matrix and a material or a raw material to be a phase mainly present in the matrix. The first step of producing (1) a raw material composed of aluminum and a rare earth element, (2) a raw material composed of aluminum and a titanium group element, or (3) a raw material composed of aluminum, a rare earth element and a titanium group element. As the aluminum powder mainly to be the matrix from the raw material produced in the first step, and the alloy powder to be the material or phase mainly present in the matrix, (1) an alloy of aluminum and a rare earth element. Powder (aluminum-rare earth element), (2) alloy powder of aluminum and titanium group element (aluminum-titanium group element), or (3) alloy powder of aluminum, rare earth element and titanium group element (aluminum-rare earth element) -Titanium group element), and from the powder obtained in the second step, (1) aluminum and aluminum-rare earth element sintered body, (2) aluminum and aluminum-titanium group element baking. It has a third step of obtaining an alloy or (3) a sintered body of aluminum and aluminum-rare earth element-titanium group element.

[First step]
This step is a step of producing a raw material used for producing an alloy powder of aluminum-rare earth element, an alloy powder of aluminum-titanium group element or an alloy powder of aluminum-rare earth element-titanium group element in the second step. .. As the raw material for producing powder (hereinafter, also simply referred to as “raw material”) produced in the first step, (1A) single metals of the constituent elements of the alloy target are prepared as starting raw materials, and these are mixed. The form used as a raw material, (2A) an alloy having the same composition as the alloy target is prepared as a starting raw material and used as a raw material, or (3A) the alloy target and the constituent elements are the same or partially missing as the starting raw material. Examples thereof include an alloy in which the composition ratio is different from the desired composition ratio and a single metal to be blended to adjust the composition to the desired composition, which are mixed and used as a raw material. As a starting material, either aluminum and rare earth elements, aluminum and titanium group elements, or aluminum and rare earth elements and titanium group elements are put into a melting device and melted to form a raw material for an alloy of aluminum-rare earth elements, aluminum-titanium. A raw material for a group element alloy or a raw material for an aluminum-rare earth element-titanium group element alloy is produced. After melting, the melting device is used to prevent a large amount of impurities from being mixed into the raw material of the alloy of aluminum-rare earth element, the raw material of the alloy of aluminum-titanium group element, or the raw material of the alloy of aluminum-rare earth element-titanium group. It is preferable to use a material with few impurities for the equipment and container to be used. As the melting method, a method that can cope with the following melting temperatures is selected. As the melting temperature, an aluminum-rare earth element alloy is heated at 1300 to 1800 ° C., an aluminum-titanium group element alloy at 1300 to 1800 ° C., or an aluminum-rare earth element-titanium group element alloy is heated at 1300 to 1800 ° C. The atmosphere in the melting device is a vacuum atmosphere having a vacuum degree of 1 × 10 ⁻² Pa or less, a nitrogen gas atmosphere containing 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 4 vol% or less of hydrogen gas. When the raw material for aluminum is produced, such as when the aluminum matrix is contained in the target, the aluminum is heated at 700 to 900 ° C. and charged into a melting device to produce the same as other raw materials.

The form of the raw material of the alloy powder may be an alloy grain or an alloy ingot, or a combination of the powder, the grain and the agglomerate, in addition to the three raw material forms described in (1A), (2A) and (3A) above. May be good. The powder, the grain, and the lump express the difference in the particle size, but in any case, the particle size is not particularly limited as long as it can be used in the powder production apparatus according to the second step. Specifically, since the raw material is melted in the powder manufacturing apparatus of the second step, there is no particular limitation as long as the size of the raw material can be supplied to the powder manufacturing apparatus.

[Second step]
This step is a step of producing an alloy powder of aluminum-rare earth element, an alloy powder of aluminum-titanium group element, or an alloy powder of aluminum-rare earth element-titanium group element. At least one of the raw materials for the aluminum-rare earth element alloy, the aluminum-titanium group element alloy, or the aluminum-rare earth element-titanium group alloy material produced in the first step is used as a powder manufacturing apparatus. After being charged and melted to form a molten metal, gas or water is sprayed on the molten metal to scatter the molten metal and quench and solidify to prepare a powder. After melting, use the powder manufacturing equipment to prevent a large amount of impurities from being mixed into the aluminum-rare earth element alloy powder, aluminum-titanium group element alloy powder, or aluminum-rare earth element-titanium group element alloy powder. It is preferable to use a material with few impurities for the equipment and container to be used. As the melting method, a method that can cope with the following melting temperatures is selected. As for the melting temperature, the raw material of the alloy of aluminum-rare earth element at 1300 to 1800 ° C, the raw material of the alloy of aluminum-titanium group at 1300 to 1800 ° C, or the raw material of aluminum-rare earth element-titanium group at 1300 to 1800 ° C. Heat the raw material of the alloy. The atmosphere in the powder manufacturing apparatus is a vacuum atmosphere having a vacuum degree of 1 × 10 ⁻² Pa or less, a nitrogen gas atmosphere containing 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 4 vol% or less of hydrogen gas. The temperature of the molten metal when spraying should be "the melting point of each of the alloy of aluminum-rare earth element, alloy of aluminum-titanium group element, or alloy of aluminum-rare earth element-titanium group element + 100 ° C or higher". Is preferable, and it is more preferable to carry out at the melting point of each of the alloy of aluminum-rare earth element, the alloy of aluminum-titanium group element, or the alloy of aluminum-rare earth element-titanium group element + 150 to 250 ° C. This is because if the temperature is too high, cooling during granulation is not sufficiently performed, it is difficult to form powder, and production efficiency is not good. Further, if the temperature is too low, a problem that nozzle clogging at the time of injection is likely to occur tends to occur. Nitrogen, argon, etc. are used as the gas for spraying, but the gas is not limited to this. In the case of alloy powder, the precipitation of intermetallic compounds in the alloy powder is suppressed by quenching and solidification as compared with the case of the dissolution method, and the diameter of the precipitated particles corresponding to the islands of the sea island structure may become smaller, and the alloy powder The state is already obtained at the stage of, and is maintained even after sintering or when a target is formed. The rapidly cooled powder has an element ratio of aluminum and rare earth elements, aluminum and titanium group elements, or aluminum and rare earth elements and titanium group elements prepared in the first step. When an aluminum powder is produced, such as when the aluminum matrix is contained in the target, the aluminum is heated at 700 to 900 ° C. and charged into a melting device to produce the aluminum powder in the same manner as other powders.

[Third step]
This step is a step of obtaining a target sintered body from the powder obtained in the second step. As the sintering method, baking is performed by a hot press method (hereinafter, also referred to as HP), a discharge plasma sintering method (hereinafter, also referred to as SPS), or a hot isotropic pressure sintering method (hereinafter, also referred to as HIP). Make a conclusion. Sintering is performed using the aluminum-rare earth element alloy powder, the aluminum-titanium group element alloy powder, or the aluminum-rare earth element-titanium group element alloy powder obtained in the second step. The powder used for sintering is the following cases.
(1B) In the case of an aluminum-rare earth element alloy, an aluminum-rare earth element alloy powder is used.
(2B) In the case of an aluminum-titanium group element alloy, an aluminum-titanium group element alloy powder is used.
(3B) In the case of an alloy of aluminum-rare earth element-titanium group element, for example, an alloy powder of aluminum-rare earth element-titanium group element is used, or an alloy powder of aluminum-rare earth element and an alloy powder of aluminum-titanium group element are used. A mixed powder in which the above two types are mixed is used.
It is preferable that any of the powders shown in (1B) to (3B) is packed in a mold, the powder is sealed with a mold and a punch or the like with a preliminary pressure of 10 to 30 MPa, and then sintered. At this time, the sintering temperature is preferably 700 to 1300 ° C., and the pressing force is preferably 40 to 196 MPa. The atmosphere in the sintering apparatus is a vacuum atmosphere having a vacuum degree of 1 × 10 ⁻² Pa or less, a nitrogen gas atmosphere containing 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 4 vol% or less of hydrogen gas. It is preferable that hydrogen gas is contained in an amount of 0.1 vol% or more. The holding time (holding time of the maximum temperature of the sintering temperature) is preferably 2 hours or less, more preferably 1 hour or less, and further preferably no holding time. When the aluminum powder is mixed with the alloy powder of (1B), (2B) or (3B) above, such as when the aluminum matrix is contained in the target, the sintering temperature is 500 to 600 ° C. It is preferable to sinter under the same conditions.

By going through at least the first step to the third step, it is possible to produce a sputtering target in which the composition deviation in the in-plane direction and the thickness direction of the sputtering target is suppressed and the content of impurities affecting the thin film formation is small. Further, it is possible to prepare a sputtering target having a low fluorine content.

The method for manufacturing a sputtering target according to the present embodiment also includes the following modifications. That is, in the first step, the aluminum raw material mainly to be the mother phase and the material mainly present in the mother phase or the raw material to be the phase are (1) a rare earth element raw material, (2) a titanium group element raw material, or (3) A raw material composed of a rare earth element and a titanium group element may be produced. In the second step, each of the raw materials produced in the first step may be atomized powder. In the third step, (1) a sintered body of aluminum and a rare earth element, (2) a sintered body of aluminum and a titanium group element, or a sintered body of aluminum and a titanium group element from the raw material obtained in the first step or the powder obtained in the second step. (3) A sintered body of aluminum and a rare earth element-titanium group element is obtained.

In the present embodiment, the methods of composition analysis in (Condition 1) and (Condition 2) are energy dispersive X-ray spectroscopy (EDS), high frequency inductively coupled plasma emission spectroscopy (ICP), and fluorescent X-ray analysis. XRF) and the like, but composition analysis by EDS is preferable.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not construed as being limited to the examples.

(Example 1)
The Al raw material with a purity of 4N and the Sc raw material with a purity of 3N are put into the powder manufacturing apparatus, and then the inside of the powder manufacturing apparatus is adjusted to a vacuum atmosphere of 5 × 10 ^-3 Pa or less, and the Al raw material is prepared at a melting temperature of 1700 ° C. The Sc raw material is melted to form a molten metal, and then argon gas is sprayed onto the molten metal to scatter the molten metal and quench and solidify to obtain an Al-40 atomic% Sc powder having a particle size of 150 μm or less (in this case, Al is 60 atoms). Although it is% Al, the description of the atomic percentage of Al is omitted. The same shall apply hereinafter) was prepared. Then, Al-40 atomic% Sc powder was filled in a carbon mold for discharge plasma sintering (hereinafter, also referred to as SPS sintering). Next, the mixed powder was sealed with a mold and a punch by prepressing 10 MPa, and the mold filled with the mixed powder was installed in an SPS device (model number: SPS-825, manufactured by SPS Syntex). The sintering conditions are a sintering temperature of 550 ° C., a pressing force of 30 MPa, a vacuum atmosphere of 8 × 10 ^-3 Pa or less, and a holding time of the maximum sintering temperature of 0 hours. Sintering was carried out in. The Al-40 atomic% Sc sintered body was processed using a grinding machine, a lathe, or the like to prepare an Al-40 atomic% Sc target having a diameter of 50.8 mm × 5 mmt according to Example 1. Next, the cross section of the Al-40 atomic% Sc target was observed using an electron microscope at a magnification of 500 times. The observed electron microscope image is shown in FIG. The length of the lateral side of the image of FIG. 7 is 250 μm. As a result of FIG. 7, it was confirmed that the contrast was small in shade and the intermetallic compound was fine and uniformly dispersed. Further, as a result of the electron microscope image of FIG. 7, the target was composed of two kinds of intermetallic compounds, Al ₂ Sc and Al Sc, and had the first structure. Next, the fluorine content of the Al-40 atomic% Sc target of Example 1 was measured using a mass spectrometer (model number: Element GD, manufactured by Thermo Fisher Scientific). The fluorine content was 5.5 ppm. Next, using the Al-40 atomic% Sc target of Example 1, a film was formed on a single crystal Si substrate of Φ76.2 mm × 5 mmt using a sputtering device (model number MPS-6000-C4, manufactured by ULVAC). As for the film forming conditions, the pressure inside the sputtering apparatus was adjusted to 0.13 Pa using Ar gas after the inside of the sputtering apparatus was evacuated and the ultimate vacuum before film formation reached 5 × 10 ^-5 Pa or less. Then, the sputter power of the Al-40 atomic% Sc target was adjusted to 150 W while heating the single crystal Si substrate to 300 ° C., and an Al-40 atomic% Sc film having a thickness of 1 μm was formed on the single crystal Si substrate. At this time, the state of sputtering of the Al-40 atomic% Sc target was observed, but the voltage was stable and an abnormal discharge was not confirmed, and the film could be formed.

(Example 2)
In Example 1, an Al-30 atomic% Sc powder having a particle diameter of 150 μm or less was produced in place of the Al-40 atomic% Sc powder, and Φ50.8 mm × was used in place of the Al-40 atomic% Sc target of Example 1. An Al-30 atomic% Sc target of Example 2 was obtained in the same manner except that a 5 mmt Al-30 atomic% Sc target was produced. Next, the fluorine content of the Al-30 atomic% Sc target of Example 2 was measured in the same manner as in Example 1. The fluorine content was 22 ppm. The target consisted of two intermetallic compounds, Al ₂ Sc and Al Sc, and had a first structure. Next, Al-30 was placed on the single crystal Si substrate in the same manner as in Example 1 except that the Al-30 atomic% Sc target of Example 2 was used instead of the Al-40 atomic% Sc target of Example 1. An atomic% Sc film was formed with a thickness of 1 μm. At this time, the state of sputtering of the Al-30 atomic% Sc target was observed, but the voltage was stable and an abnormal discharge was not confirmed, and the film could be formed.

(Example 3)
In Example 1, Al-40 atoms having a particle size of 150 μm or less are used in the same manner except that an Al raw material having a purity of 4N and a Ti raw material having a purity of 3N are used instead of using an Al raw material having a purity of 4N and a Sc raw material having a purity of 3N. % Ti powder was prepared. Next, Al-40 of Example 3 was produced in the same manner as in Example 1 except that an Al-40 atomic% Ti target having a diameter of 50.8 mm × 5 mmt was produced instead of the Al-40 atomic% Sc target of Example 1. Atomic% Ti targets were obtained. Next, the fluorine content of the Al-40 atomic% Ti target of Example 3 was measured in the same manner as in Example 1. The fluorine content was 14 ppm. The target consisted of two intermetallic compounds, Al ₂ Ti and Al Ti, and had a first structure. Next, Al-40 was placed on the single crystal Si substrate in the same manner as in Example 1 except that the Al-40 atomic% Ti target of Example 3 was used instead of the Al-40 atomic% Sc target of Example 1. An atomic% Ti film was formed with a thickness of 1 μm. At this time, the state of sputtering of the Al-40 atomic% Ti target was observed, but the voltage was stable and an abnormal discharge was not confirmed, and the film could be formed.

(Comparative Example 1)
Using pure Al powder with a particle size of 150 μm or less and a purity of 3N and Sc powder with a particle size of 150 μm or less and a purity of 2N, the amount of each powder is adjusted to be Al-40 atomic% Sc, and then mixed. rice field. Then, Al-40 atomic% Sc mixed powder was filled in a carbon mold for SPS sintering. Next, the mixed powder was sealed with a mold and a punch by prepressing 10 MPa, and the mold filled with the mixed powder was installed in an SPS device (model number: SPS-825, manufactured by SPS Syntex). The sintering conditions are a sintering temperature of 550 ° C., a pressing force of 30 MPa, a vacuum atmosphere of 8 × 10 ^-3 Pa or less, and a holding time of the maximum sintering temperature of 0 hours. Sintering was carried out in. The sintered Al-40 atomic% Sc sintered body was processed using a grinding machine, a lathe, or the like to prepare a Φ50.8 mm × 5 mmt Al-40 atomic% Sc target of Comparative Example 1. Next, the fluorine content of the Al-40 atomic% Sc target of Comparative Example 1 was measured in the same manner as in Example 1. The fluorine content was 130 ppm. The target consisted of two intermetallic compounds, Al ₂ Sc and Al Sc, and had a first structure. Next, Al-40 was placed on the single crystal Si substrate in the same manner as in Example 1 except that the Al-40 atomic% Sc target of Comparative Example 1 was used instead of the Al-40 atomic% Sc target of Example 1. An atomic% Sc film was formed with a thickness of 1 μm. At this time, the state of sputtering of the Al-40 atomic% Sc target of Comparative Example 1 was observed, but the voltage was not stable and abnormal discharge was confirmed. It is considered that the cause of the abnormal discharge as compared with Example 1 is that the fluorine in the sputtering target was released by heating at the time of film formation.

(Comparative Example 2)
In Comparative Example 1, the Al-40 atomic% Sc target of Comparative Example 1 was replaced in the same manner except that the amount of each powder was adjusted to be Al-30 atomic% Sc instead of Al-40 atomic% Sc. In addition, an Al-30 atomic% Sc target of Φ50.8 mm × 5 mmt of Comparative Example 2 was prepared. Next, the fluorine content of the Al-30 atomic% Sc target of Comparative Example 2 was measured in the same manner as in Example 1. The fluorine content was 180 ppm. The target consisted of two intermetallic compounds, Al ₂ Sc and Al Sc, and had a first structure. Next, Al-30 was placed on the single crystal Si substrate in the same manner as in Example 1 except that the Al-30 atomic% Sc target of Comparative Example 2 was used instead of the Al-40 atomic% Sc target of Example 1. An atomic% Sc film was formed with a thickness of 1 μm. At this time, the state of sputtering of the Al-30 atomic% Sc target of Comparative Example 2 was observed, but the voltage was not stable and abnormal discharge was confirmed. It is considered that the cause of the abnormal discharge as compared with Example 2 is that the fluorine in the sputtering target was released by heating at the time of film formation.

(Comparative Example 3)
In Comparative Example 1, the amount of each powder is adjusted to be Al-40 atomic% Sc using a pure Al powder having a particle size of 150 μm or less and a purity of 3N and a Sc powder having a particle size of 150 μm or less and a purity of 2N. Instead, the amount of each powder was adjusted to be Al-40 atomic% Ti using a pure Al powder having a particle size of 150 μm or less and a purity of 3N and a Ti powder having a particle size of 150 μm or less and a purity of 2N. Similarly, a Φ50.8 mm × 5 mmt Al-40 atomic% Ti target of Comparative Example 3 was prepared. Next, the fluorine content of the Al-40 atomic% Ti target of Comparative Example 3 was measured in the same manner as in Example 1. The fluorine content was 190 ppm. The target consisted of two intermetallic compounds, Al ₂ Ti and Al Ti, and had a first structure. Next, Al-40 was placed on the single crystal Si substrate in the same manner as in Example 1 except that the Al-40 atomic% Ti target of Comparative Example 3 was used instead of the Al-40 atomic% Sc target of Example 1. An atomic% Ti film was formed with a thickness of 1 μm. At this time, the state of sputtering of the Al-40 atomic% Ti target of Comparative Example 3 was observed, but the voltage was not stable and abnormal discharge was confirmed. It is considered that the cause of the abnormal discharge as compared with Example 3 is that the fluorine in the sputtering target was released by heating at the time of film formation.

(Comparative Example 4)
The Al raw material with a purity of 4N and the Sc raw material with a purity of 3N were weighed so as to have Al-40 atomic% Sc, and melted with an arc melting device (AME-300 type manufactured by ULVAC) to dissolve about 60 mm square x 6 mm. I got a board. Next, I tried to machine this plate to make a sputtering target of Φ50.8mm × 5mmt, but the outer circumference of the plate was chipped in the grinding process, and cracks occurred in the plate in the cutting process by wire electric discharge machining. , The sputtering target could not be prepared. In order to confirm the cause of the crack, the cross section of the Al-40 atomic% Sc target was observed at a magnification of 500 times using an electron microscope. The observed electron microscope image is shown in FIG. The length of the lateral side of the image of FIG. 8 is 250 μm. As a result of FIG. 8, the discontinuous surface at the upper end is the target machined surface, but cracks were confirmed inside the intermetallic compound. Therefore, it is probable that cracks are likely to occur starting from the coarsened particles of the intermetallic compound, resulting in poor processability.

Table 1 shows the types of elements added to Al, the amount of added elements added, and the content of fluorine for Examples 1 to 3 and Comparative Examples 1 to 3. By comparing Example 1 and Comparative Example 1, Example 2 and Comparative Example 2, and Example 3 and Comparative Example 3, even if the type and amount of the added element to Al are the same, as described above. It was found that if the fluorine content was not a predetermined value (100 ppm or less), an abnormal discharge would occur during film formation.

In Comparative Example 4, since the plate was prepared only by the dissolution method, the obtained plate had a texture in which the intermetallic compound was coarsened. Therefore, the intermetallic compound becomes brittle, and it is considered that chips and cracks occur during processing starting from this brittle intermetallic compound. On the other hand, in Example 1, granulation by dissolution and quenching and solidification suppresses the formation of coarsened intermetallic compounds, and then a sputtering target is produced through a process called sintering, which is fine. It is considered that the structure is maintained, chipping and cracking are suppressed, and workability is improved. In the sputtering target of Example 1, the composition deviation depending on the location in the target is small because the fine structure is maintained. In order to confirm the composition deviation, the composition in the sputtering surface inward direction and the target thickness direction of the sputtering target in (Condition 1) was confirmed. The composition was measured using EDS (manufactured by JEOL Ltd.). As a result, it was confirmed that the difference was within ± 1% with respect to the standard composition in each case, and the composition deviation was small. On the other hand, in Comparative Example 4, it was found that the difference was not within ± 3% with respect to the reference composition depending on the measurement points, and the composition deviation was large as compared with Example 1.

In Example 1, the chlorine content was measured using a mass spectrometer (model number: Element GD, manufactured by Thermo Fisher Scientific). The chlorine content was 5.6 ppm. Further, in Comparative Example 1, the chlorine content was measured in the same manner. The chlorine content was 146 ppm.

In Example 1, the oxygen content was measured using a mass spectrometer (model number: ON836, manufactured by LECO). The oxygen content was 424 ppm. Further, in Comparative Example 1, the oxygen content was measured in the same manner. The oxygen content was 2993 ppm.

(Example 4)
Using pure Al powder having a particle diameter of 150 μm or less and a purity of 4 N and ScN powder having a particle diameter of 150 μm or less and a purity of 3 N, the amount of each powder was adjusted to be Al-10 mol% ScN and then mixed. .. Then, the Al-10 mol% ScN mixed powder was filled in a carbon mold for discharge plasma sintering (hereinafter, also referred to as SPS sintering). Next, the mixed powder was sealed with a mold and a punch by prepressing 10 MPa, and the mold filled with the mixed powder was installed in an SPS device (model number: SPS-825, manufactured by SPS Syntex). The sintering conditions are a sintering temperature of 550 ° C., a pressing force of 30 MPa, a vacuum atmosphere of 8 × 10 ^-3 Pa or less, and a holding time of the maximum sintering temperature of 0 hours. Sintering was carried out in. The sintered Al-10 mol% ScN sintered body was processed using a grinding machine, a lathe, or the like to prepare an Al-10 mol% ScN target having a diameter of 50 mm × 6 mmt. At the time of producing the target, the workability was good and it was possible to mold into the target shape. The surface of the prepared target was observed with a microscope. The observed image is shown in FIG. The length of the lateral side of the image of FIG. 9 is 650 μm. From FIG. 9, it can be confirmed that Al occupies most of ScN, and it is considered that the aluminum matrix is present due to the presence of the connected Al. As a result, it is considered that the processability at the time of producing the target was obtained. At this time, the target consisted of two phases, Al and ScN, and had a fifth tissue-2.

Next, the fluorine content of the Al-10 mol% ScN target of Example 4 was measured using a mass spectrometer (model number: Element GD, manufactured by Thermo Fisher Scientific). The fluorine content was 4.1 ppm.

Next, using the Al-10 mol% ScN target of Example 4, a film was formed on a single crystal Si substrate of Φ76.2 mm × 5 mmt using a sputtering device (model number MPS-6000-C4, manufactured by ULVAC). As for the film forming conditions, the pressure inside the sputtering apparatus was adjusted to 0.13 Pa using Ar gas after the inside of the sputtering apparatus was evacuated and the ultimate vacuum before film formation reached 5 × 10 ^-5 Pa or less. Then, the sputter power of the Al-10 mol% ScN target was adjusted to 150 W while heating the single crystal Si substrate to 300 ° C., and an Al-10 mol% ScN film having a thickness of 1 μm was formed on the single crystal Si substrate. At this time, the state of sputtering of the Al-10 mol% ScN target was observed, but the voltage was stable and an abnormal discharge was not confirmed, and the film could be formed.

100,200,300,400 Sputtering target O Center L, Q Virtual cross line S1 to S9 Sputtering surface measurement points C1 to C9 Cross section measurement points P1 to P9 Sputtering surface measurement points D1 to D9 Cross section measurement points 1 Al- RE alloy particles 3 Al matrix 2, 2a, 2b Al-RE alloy crystal grains 4, 4a, 4b Aluminum crystal grains

Claims (9)

A sputtering target containing aluminum and further containing one or both of a rare earth element and a titanium group element.
A sputtering target characterized by a fluorine content of 100 ppm or less. The sputtering target according to claim 1, wherein the chlorine content is 100 ppm or less. The sputtering target according to claim 1 or 2, wherein the oxygen content is 500 ppm or less. The invention according to any one of claims 1 to 3, wherein an intermetallic compound composed of at least two elements selected from aluminum, a rare earth element and a titanium group element is present in the sputtering target. Sputtering target. The sputtering target according to claim 4, wherein the intermetallic compound is present in the sputtering target in one type, two types, three types or four types. One of claims 1 to 5, wherein the sputtering target contains at least one nitride of at least one element selected from aluminum, a rare earth element, and a titanium group element. The sputtering target described. The sputtering target according to any one of claims 1 to 6, wherein the rare earth element is at least one of scandium and yttrium. The sputtering target according to any one of claims 1 to 7, wherein the titanium group element is at least one of titanium, zirconium, and hafnium. A structure in which at least one of a material containing aluminum and a rare earth element, a material containing aluminum and a titanium group element, and a material containing aluminum, a rare earth element, and a titanium group element is present in the aluminum matrix. Have or
A structure composed of a composite phase in which at least one or both of a phase containing only rare earth elements and unavoidable impurities as metal species and a phase containing only titanium group elements and unavoidable impurities as metal species are contained in the aluminum matrix. The sputtering target according to any one of claims 1 to 8, wherein the sputtering target comprises.

Images