KR20130133002A - High purity ni sputtering target and method for manufacturing same - Google Patents

Abstract

The present invention is a high-purity Ni sputtering target having an average crystal grain diameter of 1000 µm or less, the crystal orientation in the sputter surface is random orientation, and the crystal orientation in the center plane in the thickness direction of the sputtering target is also random orientation. It is a high-purity Ni sputtering target. It is preferable that the order of the peaks does not change even when the powder is subjected to X-ray diffraction. According to the said structure, stable sputter rate can be obtained and the high purity Ni sputtering target which can be used for a long time is obtained.

Description

High purity Ni sputtering target and manufacturing method thereof {HIGH PURITY Ni SPUTTERING TARGET AND METHOD FOR MANUFACTURING SAME}

The present invention relates to a high purity Ni sputtering target and a manufacturing method thereof.

High melting point metal silicide films are widely used as wiring films for semiconductor devices (including liquid crystal display devices). As a formation method of this wiring film, the method of sputtering and forming into a film the high melting-point metal silicide sputtering target was used.

As a manufacturing method of this kind of sputtering target, Unexamined-Japanese-Patent No. 2002-38260 (patent document 1) discloses manufacturing a target by sintering silicides, such as W, Mo, and Ni. In such a metal silicide target, control of metal silicide and free Si is necessary.

On the other hand, in the semiconductor device, with the narrow pitch and the complexity of wiring, it has been attempted to heat-treat the metal film as a metal silicide film after forming the metal film. For example, in Japanese Unexamined Patent Publication No. 2009-239172 (Patent Document 2), after forming metal films such as V, Ti, Co, and Ni, heat treatment is performed at about 400 to 500 ° C. to make the metal films as metal silicide films. Rapid Thermal Annealing (RTA) method is disclosed. By this method, a metal silicide film can be formed in the target location.

Ni is attracting attention as a metal used for such a metal silicide film. For example, Japanese Unexamined Patent Application Publication No. 2008-101275 (Patent Document 3) discloses a high purity Ni sputtering target. In patent document 3, the uniformity (uniformity) of a sputtering film is improved by controlling permeability and a coarse particle.

On the other hand, since the target thickness of the patent document 3 must be 5 mm or less, the long term sputter operation was not able to be performed, and there existed a fault which has a large number of replacement | exchange of a target, and low continuous operation characteristics.

Japanese Patent Laid-Open No. 2002-38260 Japanese Patent Publication No. 2009-239172 Japanese Patent Publication No. 2008-101275

A problem in the case of producing a high purity Ni target having a thickness of 5 mm or more is crystal orientation. For example, when the crystallographic orientation of the sputter surface and the crystallographic orientation of the target center are different, the sputtering rate changes, so that there is a problem in that stable long-term sputtering characteristics cannot be obtained.

This invention is made | formed in order to solve such a problem, and it is providing the sputtering target of long-term reliability by making crystal orientation into uniform random orientation.

The 1st high purity Ni sputtering target of this invention is a high purity Ni sputtering target whose average crystal grain diameter is 1000 micrometers or less, crystal orientation in the sputter surface is random orientation, and the sputtering target in the center plane of the thickness direction Crystal orientation is also characterized by random orientation.

Moreover, the 2nd high purity Ni sputtering target of this invention is a high purity Ni sputtering target whose average crystal grain diameter is 1000 micrometers or less, The order of the height of each peak detected when X-ray diffraction of the sputter surface, and a part of a target are carried out. It is characterized by the same order of height of each peak detected when X-ray diffraction is used as a powder.

Moreover, in the said high purity Ni sputtering target, it is preferable that the said average crystal grain diameter is 20-500 micrometers. Moreover, it is preferable that the average aspect ratio of the crystal grain diameter of the said sputter surface is three or less.

In addition, it is preferable that the order of the heights of the peaks detected when the sputter surface is detected by X-ray diffraction is the same as the order of the heights of the peaks detected by X-ray diffraction when a part of the target is used as a powder.

Moreover, it is preferable that the said high purity Ni is 99.999 mass% or more. Moreover, it is preferable that the thickness of a sputtering target is 6 mm or more. In addition, when the X-ray diffraction (2θ) peak of the sputtering surface is measured, it is preferable that the order of the relative intensity ratios of (220), (200), and (111) is (220) <(200) <(111). Do.

Moreover, the manufacturing method of the high purity Ni sputtering target of this invention is a cold or hot forging process which presses the Ni material which consists of a cylindrical high purity Ni ingot or a billet in the direction parallel to a thickness direction, and is perpendicular | vertical to a thickness direction. A first kneading forging step of performing two or more sets of kneading forgings having one set of cold or hot forgings pressurized in a direction;

A first heat treatment step of recrystallization at a temperature of 900 ° C. or higher after the forging process;

After the first heat treatment step, a second or more performing two or more sets of kneading forgings having one set of cold or hot forging processing pressurized in a direction parallel to the thickness direction and cold or hot forging processing hitting and pressing in a direction perpendicular to the thickness direction. Kneading forging process,

A cold rolling step of performing cold rolling after the second kneading forging step,

A second heat treatment step of performing heat treatment at a temperature of 500 ° C. or higher after the cold rolling process,

It is characterized by having a.

Moreover, in the manufacturing method of the said high purity Ni sputtering target, it is preferable to perform the said cold rolling process 2 times or more. In addition, it is preferable that at least one of a 1st kneading forging process and a 2nd kneading forging process performs a cross-sectional reduction rate or a thickness reduction rate at 40% or more of processing rate. Moreover, it is preferable that the average value of the Vickers hardness Hv of the Ni alloy material after 1st kneading forging is Hv160 or more. Moreover, it is preferable that Ni raw material is 99.999 mass% or more in Ni purity.

In the high purity Ni sputtering target which concerns on this invention, since arbitrary crystal orientation is hold | maintained over the thickness direction, the sputter rate is stable over a long time. Therefore, in a sputtering process, since the number of times of target replacement | exchange is small, manufacture of a sputtering film can be performed efficiently.

Moreover, according to the manufacturing method of the high purity Ni sputtering target which concerns on this invention, the high purity Ni sputtering target of this invention can be manufactured efficiently.

1 is a perspective view illustrating a shape example of a high purity Ni sputtering target according to the present invention.
2 is a perspective view illustrating a shape example of a cylindrical Ni material.
3 is a side view illustrating a shape example in which a cylindrical Ni material is seen in a lateral direction.
4 is a plan view showing a configuration example of a cylindrical Ni material viewed from above.

The 1st high purity Ni sputtering target of this invention is a high purity Ni sputtering target whose average crystal grain diameter is 1000 micrometers or less, crystal orientation in the sputter surface is random orientation, and the sputtering target in the center plane of the thickness direction Crystal orientation is also characterized by random orientation.

Moreover, the 2nd high purity Ni sputtering target of this invention is a high purity Ni sputtering target whose average crystal grain diameter is 1000 micrometers or less, The order of the height of each peak detected when X-ray diffraction of the sputter surface, and a part of a target are carried out. It is characterized by the same order of height of each peak detected when X-ray diffraction is used as a powder.

High purity Ni (nickel) used by this invention shows Ni purity 99.99 mass% or more high purity. The measuring method of purity is Fe, Cr, Al, Co, Ti, Zr, Hf, V, Nb, Ta, Pt, Pb, Cu, Mn, Na, K, S, W, Mo, B, Ni purity is calculated | required by measuring content of P, U, and Th, respectively, and subtracting the total amount from 100 mass%. In addition, although the metal impurity is contained, in most cases, it is the trace amount which does not affect the calculation of purity.

In this invention, content of impurity metal is 0.01 mass% or less (100 wtppm or less), Preferably it is 0.001 mass% or less (10 wtppm or less). As for content of an impurity metal, 0.01 mass% or less means Ni purity 99.99 mass% or more. In addition, content of an impurity metal is 0.001 mass% or less means Ni purity 99.999 mass% or more.

Moreover, impurity gas components are mentioned as impurities other than an impurity metal. Examples of the gas component include oxygen, nitrogen, carbon, and hydrogen. The total amount of these gas components is preferably 300 wtppm or less, more preferably 150 wtppm or less.

If the impurity metal and the impurity gas components are present in a large amount, it causes a partial resistance variation of the target, and the variation of the sputter rate is large. Therefore, it is preferable that it is the range mentioned above.

In addition, the average crystal grain diameter of Ni sputtering target is 1000 micrometers or less. When the average crystal grain diameter exceeds 1000 µm, the crystals of Ni (including Ni alloy) become excessive, which causes variation in the sputter rate. Preferably, the average crystal grain diameter is 20 to 500 µm, more preferably 40 to 500 µm, and further preferably 40 to 120 µm. Moreover, it is also effective to recrystallize by heat processing as a control method of average crystal grain diameter.

The measurement of the said average crystal grain diameter takes an enlarged photograph of unit area 3000 micrometers x 3000 micrometers with an optical micrograph, and is performed by the line intercept method. The line intercept method draws an arbitrary straight line (about 3000 µm in length), counts the number of Ni crystal grains on the linear line, and calculates the average crystal grain diameter by (the number of crystals on 3000 µm / 3000 µm in a straight line). The average value which performed this operation 3 times is made into the average crystal grain diameter.

Moreover, it is preferable that the average aspect ratio of the crystal grain diameter of the sputter surface of Ni sputtering target is three or less. When average aspect ratio exceeds 3, there exists a possibility that the part which is not a random orientation in a sputter surface may be formed. It is preferable that an average aspect ratio is three or less, Furthermore, it is two or less.

In addition, the measuring method of an average aspect ratio uses the enlarged photograph used for measuring the average crystal grain diameter, measures the long axis and short axis of each crystal grain, and calculates an aspect ratio (long axis / short axis). This operation | work is performed about 100 crystal grains, and makes the average value into "average aspect ratio." In addition, the long axis is the maximum diameter of the crystal grains, and the short axis is the width of the portion lined vertically from the center of the long axis.

The high-purity Ni sputtering target according to the first invention is characterized in that the crystal orientation of the sputter surface is random orientation, and the crystal orientation in the center plane of the thickness direction of the target is also random orientation.

1 shows an example of one shape of the sputtering target of the present invention. In the figure, reference numeral 1 denotes a sputtering target, 2 denotes a sputtering surface, and T denotes the thickness of the target. In FIG. 1, although it used as the target of a column shape (disk shape), a rectangular parallelepiped may be sufficient. Any shape of a cylindrical shape and a rectangular parallelepiped may be sufficient, and you may chamfer as needed.

In the high purity Ni sputtering target 1 which concerns on 1st invention, the crystal orientation of the sputter surface 2 is a random orientation. In addition, the crystal orientation of the center plane 4 in the thickness direction of the target also indicates random orientation. As shown by the dotted line in FIG. 1, a "center plane in the thickness direction of a target" is the surface cut | disconnected in parallel with the sputter surface from the middle (T / 2 position) of the thickness T of a target. The high purity Ni sputtering target 1 is manufactured by performing plastic working, such as forging and rolling.

When plastic working is performed on a metal material, crystals tend to be oriented. On the other hand, the phenomenon in which crystal orientation differs easily in a sputter surface and inside. In contrast, in the present invention, since the sputter face is in a random orientation and the center of the target is also in a random orientation, the sputter rate is hardly changed even when used continuously for a long time.

In the state where the crystal orientation of the center plane 4 in the thickness direction of the target is also in the random orientation, the same random orientation can be confirmed by cutting out a plane parallel to the sputter surface in the center of the thickness direction of the target and performing X-ray diffraction.

Moreover, the 2nd high purity Ni sputtering target of this invention is a high purity Ni sputtering target with an average crystal grain diameter of 1000 micrometers or less, The order of the height of each peak detected when X-ray-diffraction of a sputter surface, and a part of target are powdered. In this case, the order of the heights of the peaks detected at the time of X-ray diffraction is the same.

The order of the heights of the peaks detected when the sputter surface is detected by X-ray diffraction and the order of the heights of the peaks detected by X-ray diffraction when a part of the target is used as a powder are the same. It shows what is equipped.

As the conditions for the X-ray diffraction, the general conditions that the used X-ray is Cu-Kα, the tube voltage is 40 mA, the tube current is 40 mA, the scattering slit is 0.63 mm, and the light receiving slit is 0.15 mm are applied. Shall be performed.

When X-ray diffraction of the sputtering surface is performed, random order results in that the order of relative intensity ratio (peak height) is (220) <(200) <(111).

In addition, X-ray diffraction which uses a part of target as powder is performed in the following procedures. That is, the rectangular parallelepiped of an at least 5 mm square is cut out from arbitrary places of a target, and it grind | pulverizes so that an average particle diameter may be 50-100 micrometers. This powder is obtained by X-ray diffraction to obtain an X-ray diffraction peak (PDF peak) of the powder. The measurement conditions of X-ray diffraction are performed on the same conditions as the above-mentioned.

In the present invention, the order of the heights of the peaks on the sputter face and the order of the heights of the PDF peaks are the same. Although the ratio of the height of an individual peak may differ from a sputter surface and PDF (powder), the order of the height of the detected peak is the same. As described above, the peak order of the sputtering surface is (220) <(200) <(111), and this order is maintained even if it becomes a powder (PDF peak). Even if it is powder, it is proved that the random orientation is maintained and uniform random orientation is maintained in the whole target.

In addition, the order (220) <(200) <(111) of the height of the peak in X-ray diffraction is also the same as the peak order of Ni powder commercially available. This can also be said to be a random orientation.

In addition, the random orientation in any of the sputter surfaces means that the cast structure can form a fine crystal structure free of ghost grains remaining. If ghost grains are present, it is not preferable because a part which is not partially random orientation is generated.

In the present invention, even if the thickness of the target is increased to 3 mm or more and even 6 mm or more, a target having a stable sputter rate for a long time can be obtained. In addition, although the upper limit of the thickness of a target is not specifically limited, 15 mm or less is preferable. When it exceeds 15 mm, it will become too thick and a handleability will worsen. In addition, the diameter of the target is not particularly limited, but even if the diameter is increased to 200 mm or more and more than 400 mm, a uniform random orientation can be obtained. In addition, although the upper limit of a target diameter is not specifically limited, 600 mm or less is preferable. When it exceeds 600 mm, handleability will deteriorate.

In addition, you may join a backing plate to the sputtering target of this invention as needed.

Next, a manufacturing method is demonstrated. Although the manufacturing method of the high purity Ni sputtering target of this invention is not specifically limited, The following manufacturing method is mentioned as a method for obtaining efficiently.

The manufacturing method of the high purity Ni sputtering target of this invention is a cold or hot forging process which presses the Ni material which consists of a cylindrical high purity Ni ingot or a billet in the direction parallel to a thickness direction, and a direction perpendicular | vertical to a thickness direction. A first kneading forging step of performing two or more sets of kneading forgings with one set of pressurized cold or hot forging, a first heat treatment step for recrystallization at a temperature of 900 ° C. or higher after the kneading forging step, and a thickness after the first heat treatment step. A second kneading forging step of performing two or more sets of kneading forgings in which one set of cold or hot forging is pressurized in a direction parallel to the direction and cold or hot forging is pressed in a direction perpendicular to the thickness direction; At the temperature of 500 degreeC or more after the cold rolling process which cold-rolls after a forging process, and a cold rolling process, And a second heat treatment step of heat treatment.

A Ni material including the cylindrical high purity Ni ingot or billet is, for example, a Ni material having a cylindrical shape as shown in FIG. 2. 3, the thickness H and the diameter W of the cylindrical Ni raw material 3 are shown. Although the magnitude | size of the cylindrical Ni raw material 3 is not specifically limited, The thing of thickness H which is about 20-300 mm and diameter W which is about 100-400 mm is easy to handle. In addition, the Ni material is preferably highly purified by casting such as an EB (electron beam) melting method. In addition, you may repeat 2 to 3 times of EB dissolution as needed. This is to approach the purity of the high purity Ni target which can obtain the purity of Ni material. Therefore, when Ni target of purity 99.99 wt% or more (4N or more) is needed, Ni material of high purity 99.99 wt% or more shall be used.

1st which performs two or more sets of kneading forgings which make one set the cold or hot forging process which presses a cylindrical Ni raw material in the direction parallel to a thickness direction, and the cold or hot forging process which presses in a direction perpendicular | vertical to a thickness direction. A kneading forging process is performed. The direction parallel to the thickness direction is the thickness H direction, and the direction perpendicular to the thickness direction is the diameter W direction.

When kneading forging in which the thickness H direction and the diameter W direction are forged alternately is set as one set, this shall be performed 2 or more sets. Since the kneading forging is applied with pressure from different directions, it is possible to achieve miniaturization of the crystal grain diameter and to prevent the crystal orientation from shifting in a specific direction. In addition, it is possible to reduce the casting structure of the Ni material produced by casting. The more the number of the kneading forgings is better, the higher the number of the kneading forgings, so that the manufacturing cost is increased, and cracking, wrinkles, etc. of the material are more likely to occur, so the number of kneading forgings is preferably 2 to 4 sets.

Moreover, it is preferable that the Vickers hardness Hv of Ni raw material after a 1st kneading forging process is 160 or more. By performing two or more sets of said forgings, homogenization of a structure is attained and the hardness of Ni material rises. However, when considering the manufacturing process mentioned later, even if it is less than Hv160, no further effect will be acquired, and a kneading forging process will be performed unnecessarily. Therefore, also in controlling the number of sets of 1st kneading forging, it is preferable to perform kneading forging so that it may become Vickers hardness Hv160 or more.

In addition, as shown in FIG. 4, the pressure of the diameter W direction is not always a fixed direction, but the 1st set adds a pressure from the direction of "pressure 2", and the 2nd set is from the direction of "pressure 3". It is preferable to change a pressurization direction suitably, such as adding a pressure. It is also effective to change the direction in which the pressure is added in one set. By changing the direction in which pressure is applied also in the diameter W direction, refinement | miniaturization of the crystal grain diameter can be achieved and it can prevent effectively that the crystal orientation shifts to a specific direction. The first kneading forging is preferably cold forging, but hot forging is also possible. As for the heating temperature in the case of hot forging, the range of 1000-1200 degreeC is preferable. In addition, since grain growth of crystals occurs, it is difficult to obtain a fine crystal structure with an average crystal grain diameter of 1000 µm or less.

After the first kneading forging step, a first heat treatment step of recrystallization at a temperature of 900 ° C. or higher is performed. By the first kneading forging step, the internal strain generated in the cylindrical Ni material can be removed by heat treatment and further recrystallized to obtain a uniform fine crystal structure. The heat treatment temperature is set to 950 to 1300 ° C, and is preferably performed for 1 to 10 hours. If the heat treatment temperature exceeds 1300 ° C. or the heat treatment time exceeds 10 hours, there is a fear that the growth of particles is accompanied. Preferably it is 1000-1200 degreeCx 3 to 7 hours. Moreover, as for heat processing atmosphere, the vacuum atmosphere of 0.133 Pa or less is preferable. This is because the surface may be oxidized during heat treatment in an oxygen-containing atmosphere.

After the first heat treatment step, second kneading forging is performed. The detail of kneading forging is the same as that of 1st kneading forging, and it is preferable to carry out two or more sets. Second kneading forging is also preferable 2 to 4 times. Moreover, it is preferable to change the pressure direction added in the diameter W direction in the 1st set and the 2nd set. Moreover, although it is preferable that a 2nd kneading forging process is also cold forging, hot forging is also possible. By the second kneading forging, it is possible to further advance the refinement of the crystal grain diameter.

After the second kneading forging, a cold rolling step is performed. Cold rolling is a process of plastic-processing cylindrical Ni raw material to plate shape. As needed, you may perform a cold rolling process twice or more. By a cold rolling process, it is preferable to set it as thickness of 3-20 mm, Preferably it is 6-15 mm. Cutting is performed from the sheet thickness manufactured by the cold rolling process, and it is set as the sheet thickness of a sputtering target.

In addition, it is better not to perform a heat treatment process between a 2nd kneading forging process and a cold rolling process. It is more preferable to cold-roll Ni material homogenized by the 2nd kneading forging process as it is.

In addition, although the processing rate of a 1st kneading forging process, a 2nd kneading forging process, and a cold rolling process is arbitrary, at least one process of a 1st kneading forging process, a 2nd kneading forging process, and a cold rolling process has a cross-sectional reduction rate or a thickness reduction rate. It is preferable that it is 40% or more. The cross-sectional reduction rate is a reduction rate of the cross-sectional area in the diameter W direction of the cylindrical Ni material. The thickness reduction rate is a reduction rate in the thickness H direction of the cylindrical Ni material. For example, two or more sets of 1st kneading forging processes are performed. The processing rate of 40% or more is the processing rate of the result performed per set.

It is preferable that the process of 40% or more of a working rate is a cold process. For example, after performing a 1st kneading forging process → a 1st heat treatment process → a 2nd kneading forging process, even if cold rolling of 40% or more of work rate is performed, generation | occurrence | production of internal deformation can be suppressed. When the processing rate is low, the occurrence of internal deformation can be suppressed, but each process is repeated several times, which takes too much time for production. Therefore, it is preferable to perform the process of 40% or more of processing rate in any one process. Moreover, as for the upper limit of a processing rate, 80% or less is preferable. Processing at a processing rate exceeding 80% in one process is likely to cause internal deformation, cracking, and wrinkles.

After the cold rolling step, a second heat treatment step of heat treatment at a temperature of 500 ° C. or higher is performed. As for heat processing conditions, 500-1100 degreeCx 2 to 5 hours are preferable. Moreover, as for heat processing atmosphere, the vacuum atmosphere of 0.133 Pa or less is preferable. This is because the surface may be oxidized during heat treatment in an oxygen-containing atmosphere. By the second heat treatment step, the internal strain generated by the second kneading forging step and the cold rolling step can be removed and recrystallized.

After the second heat treatment step, the shape is trimmed by cutting, such as lathe machining, as necessary. In addition, a backing plate is joined by solder | pewter bonding, diffusion bonding, etc.

With such a manufacturing method, an average crystal grain diameter can obtain 1000 micrometers or less, a fine crystal structure, and a random orientation simultaneously. In addition, formation of ghost grains in which the cast structure remains can be suppressed.

Next, the manufacturing method of a semiconductor element is demonstrated. The method for manufacturing a semiconductor device comprises the steps of sputtering a high purity Ni sputtering target of the present invention on a film containing Si as a constituent element to form a high purity Ni thin film, and performing a heat treatment to form a high purity Ni thin film as a Ni silicide film. It is characterized by having a.

Examples of the film containing Si as a constituent element include Si substrates and gate electrodes (polycrystalline Si, amorphous Si, etc.). On the film containing Si as a constituent element, a high purity Ni film is formed by magnetron sputtering using the high purity Ni sputtering target of this invention. Subsequently, heat treatment is carried out at about 400 to 500 ° C. to make the high purity Ni film react with Si to perform a Rapid Thermal Annealing (RTA) process to form a Ni silicide film.

Depending on the degree of heat treatment, part or all of the Ni film becomes a Ni silicide film. In addition, the Ni silicide film is preferably used for part or all of the gate electrode, the source electrode, and the drain electrode.

By using the high-purity Ni sputtering target of the present invention, the sputter rate can be stabilized for a long time, so that a stable high-purity Ni film can be obtained when manufacturing a semiconductor element. In addition, even if the thickness of the target is increased, the variation in the sputter rate is small, so that the number of replacement of the target can be reduced, and thus the manufacturing efficiency of the semiconductor element can be significantly improved.

(Example)

(Examples 1 to 6 and Comparative Example 1)

The high purity Ni raw material of diameter W100-300 mm x thickness H100-200 mm high-purified by EB melt | dissolution was prepared, and the manufacturing process shown in Table 1 was implemented. In addition, in Table 1, the processing rate (%) described the larger value among at least one of the cross-sectional reduction rate (%) of the diameter W direction, or the thickness reduction rate (%) of the thickness H direction.

In addition, Ni material was 20 wtppm or less of oxygen, 10 wtppm or less of nitrogen, 10 wtppm or less of carbon, and content of impurity metal was 10 wtppm or less in total.

The high-purity Ni material which passed the manufacturing process of the said Table 1 was lathed, and the sputtering target of the size shown in Table 2 was manufactured. The average crystal grain diameter (micrometer) in each target and the presence or absence of random orientation were confirmed. The measurement of an average crystal grain diameter took the enlarged photograph (optical microphotograph) of unit area 3000 micrometers x 3000 micrometers from the sputter surface and the cross section, and calculated | required by the line intercept method (average of three straight lines). About the measurement of Ni crystal grains, 100 aspect ratios were calculated | required from the enlarged photograph mentioned above, and the average value was shown. In the presence or absence of random orientation, X-ray diffraction analysis (2θ) was performed by selecting an arbitrary measurement location from a surface cut out parallel to the sputter surface of the center of the target thickness from the sputter surface and the sputter surface. In addition, X-ray diffraction was performed with Cu-K (target Cu), a tube voltage of 40 mA, a tube current of 40 mA, a scattering slit 0.63 mm, and a light receiving slit 0.15 mm.

The analysis results are shown in Table 2. In addition, all crystal structures were recrystallized.

In addition, a 5 mm square sample was cut out from the target, ground to an average particle diameter of 80 µm, and subjected to X-ray diffraction to determine the order of the detected peaks. The results are shown in Table 3.

Comparing Table 2 and Table 3, the order of the detected peaks was consistent. In addition, the peak order of (220) <(200) <(111) is also consistent with the peak order of commercially available Ni powder.

(Examples 7 to 10)

The high purity Ni raw material of diameter W200-300 mm x thickness H100-150 mm high-purified by EB melt | dissolution was prepared, and the manufacturing process shown in following Table 4 was implemented. In addition, in Table 4, the processing rate (%) described the larger value among at least one of the cross-sectional reduction rate (%) of the diameter W direction, or the thickness reduction rate (%) of the thickness H direction.

The Ni material had an oxygen content of 20 wtppm or less, a nitrogen content of 10 wtppm or less, a carbon content of 10 wtppm or less, and the impurity metal content was 10 wtppm or less in total.

The measurement similar to Example 1 was performed about the Ni sputtering target which concerns on Examples 7-10. The results are shown in Table 5.

In addition, a 5 mm square sample was cut out from the target, ground to an average particle diameter of 80 µm, and subjected to X-ray diffraction to determine the order of the detected peaks. The results are shown in Table 6.

Comparing Table 5 and Table 6, the order of the detected peaks was consistent. In addition, the peak order of (220) <(200) <(111) is also consistent with the peak order of commercially available Ni powder.

Next, the magnetron sputtering process was performed using the target of each Example and a comparative example. When the Ni film thickness when the target was consumed 0.5 mm from the start of sputtering was 100, the film thicknesses after 2 mm consumption and 5 mm consumption were compared.

As apparent from the results shown in Table 7, the target according to each of the examples showed that the sputter rate change was small even when used for a long time. From this result, it can be seen that the target of the present embodiment has high long-term reliability even with a thicker thickness.

1: Sputtering Target
2: sputter surface
3: Ni material
T: thickness of the sputtering target
W: diameter of Ni material
H: Thickness of Ni material (height)

Claims (15)

High purity Ni sputtering target whose average crystal grain diameter is 1000 micrometers or less, The crystal orientation in the sputter surface is random orientation, The crystal orientation in the center surface of the thickness direction of a sputtering target is also random orientation, High purity Ni characterized by the above-mentioned. Sputtering Target. It is a high purity Ni sputtering target having an average crystal grain diameter of 1000 μm or less, and the order of the heights of the peaks detected when the sputter surface is X-ray diffracted, and the peaks detected when X-ray diffraction is performed using a portion of the target as a powder. The high purity Ni sputtering target characterized by the same order of height. 3. The method according to claim 1 or 2,
Said average crystal grain diameter is 20-500 micrometers, High purity Ni sputtering target characterized by the above-mentioned. 4. The method according to any one of claims 1 to 3,
A high purity Ni sputtering target, wherein the average aspect ratio of the crystal grain diameter of the sputter surface is 3 or less. 5. The method according to any one of claims 1 to 4,
A high purity Ni sputtering target, wherein the order of the heights of the peaks detected when the sputter surface is detected by X-ray diffraction is the same as the order of the heights of the peaks detected by X-ray diffraction when a part of the target is used as a powder. The method according to any one of claims 1 to 5,
The said high purity Ni is 99.999 mass% or more, The high purity Ni sputtering target characterized by the above-mentioned. 7. The method according to any one of claims 1 to 6,
The thickness of the said sputtering target is 6 mm or more, The high purity Ni sputtering target characterized by the above-mentioned. 8. The method according to any one of claims 1 to 7,
When the X-ray diffraction (2θ) peak of the sputter surface is measured, the order of the relative intensity ratios of (220), (200), and (111) is (220) <(200) <(111), High purity Ni sputtering target. Kneading comprising one set of cold or hot forging for pressurizing a Ni material including a cylindrical high purity Ni ingot or billet in a direction parallel to the thickness direction and a cold or hot forging for pressing in a direction perpendicular to the thickness direction A first kneading forging step of performing two or more sets of forgings,
A first heat treatment step of recrystallization at a temperature of 900 ° C. or higher after the forging process;
After the first heat treatment step, a second or more performing two or more sets of kneading forgings having one set of cold or hot forging processing pressurized in a direction parallel to the thickness direction and cold or hot forging processing hitting and pressing in a direction perpendicular to the thickness direction. Kneading forging process,
A cold rolling step of performing cold rolling after the second kneading forging step,
After the cold rolling step, the second heat treatment step of heat treatment at a temperature of 500 ℃ or more
Method for producing a high purity Ni sputtering target comprising a. 10. The method of claim 9,
A method for producing a high purity Ni sputtering target, wherein the cold rolling step is performed two or more times. 11. The method according to claim 9 or 10,
At least one of the said 1st kneading forging process and the 2nd kneading forging process is a cross-sectional reduction rate or a thickness reduction rate performed at 40% or more of processing rates, The manufacturing method of the high purity Ni sputtering target characterized by the above-mentioned. 12. The method according to any one of claims 9 to 11,
The average value of the Vickers hardness Hv of the Ni alloy material after the first kneading forging is Hv 160 or more, characterized in that the manufacturing method of high purity Ni sputtering target 13. The method according to any one of claims 9 to 12,
The said Ni raw material is 99.999 mass% or more of Ni purity, The manufacturing method of the high purity Ni sputtering target characterized by the above-mentioned. 14. The method according to any one of claims 9 to 13,
The obtained high purity Ni sputtering target is 1000 micrometers or less in average crystal grain diameter, The manufacturing method of the high purity Ni sputtering target characterized by the above-mentioned. 15. The method according to any one of claims 9 to 14,
The obtained high purity Ni sputtering target is a mean aspect ratio of 3 or less of crystal grains of a sputter surface, The manufacturing method of the high purity Ni sputtering target characterized by the above-mentioned.

Images