JP5550328B2 - Mo sputtering target and manufacturing method thereof - Google Patents

Description

The present invention relates to a Mo sputtering target for forming a wiring of a semiconductor device, a liquid crystal display device or the like and a method for manufacturing the same.

A refractory metal such as tungsten or molybdenum is used for wiring of a semiconductor device or a liquid crystal display device. For these wirings, a film forming method called a sputtering method is used. The sputtering method is a method for obtaining a target metal film by hitting Ar ions against a sputtering target.
A conventional tungsten or molybdenum target is disclosed, for example, in Japanese Patent No. 3244167 (Patent Document 1) by pressure sintering to obtain an average particle size of 10 μm or less and a relative density of 9
9% or more target has been obtained.
In recent years, in order to reduce the size of semiconductor devices, wiring pitches have been narrowed (downsized). In order to reduce the size of the wiring, it is effective to use a wiring material having a low resistance. Referring to the physics and chemistry dictionary and the like, the specific resistance value of tungsten is 5.65 × 10 ⁻⁶ Ωcm, while the specific resistance value of molybdenum is 5.2 × 10 ⁻⁶ Ωcm. Therefore, in general, molybdenum has a lower resistance wiring than tungsten.
In patent document 1, the target is obtained by pressure-sintering Mo powder, such as HIP. With this method, it is possible to obtain a sputtering target having a small average particle diameter and a high density.

Japanese Patent No. 3244167

The sputtering method is a method in which an Ar ion is hit against a target, and atoms of the target material are blown by the impact to form a film. Therefore, the target structure needs to be uniform in order to form a film stably for a long period of time. However, just by pressure sintering as in Patent Document 1, a non-uniform portion is formed in the structure and the sputtering rate changes. There were problems such as. In particular, when the target is increased in size, the problem due to the non-uniformity of the structure becomes remarkable.
In view of such problems, the present invention provides a Mo sputtering target having a uniform structure and a method for producing the same.

The first Mo sputtering target of the present invention is a Mo sputtering target having a purity of 99.9% or more, the average crystal grain size is 60 μm or less, the average Vickers hardness Hv of the sputtering surface is 150 to 200, and the variation of the Vickers hardness Hv is ± Within 10% , the sputter surface is characterized in that crystals having an aspect ratio of 3 or less have an area ratio of 70% or more .
Moreover, it is preferable not to have a fibrous structure . Also, it is preferable that the diameter is not less than 320 mm. Moreover, it is preferable that it is a recrystallized structure.
Moreover, when the X-ray diffraction of the sputter surface is performed, the relative intensity of the peaks of each surface of (110), (200), (211), (310) is (110)>(211)> ((200) or It is preferable to decrease in the order of (310)) .
When the second Mo sputtering target of the present invention is an Mo sputtering target having a purity of 99.9% or more, the average crystal grain size is 60 μm or less, and X-ray diffraction of the sputtering surface is performed (110), (200), The relative intensity of the peaks on each surface of (211) and (310) decreases in the order of (110)>(211)> ((200) or (310)).

In addition, the first Mo sputtering target manufacturing method of the present invention has a purity of 99.9% or more, an average crystal grain size of 60 μm or less, an average Vickers hardness Hv of the sputtering surface of 150 to 200, and a variation in Vickers hardness Hv of ± Within 10%, the sputtering surface is a method of manufacturing a Mo sputtering target in which crystals with an aspect ratio of 3 or less are 70% or more in area ratio, the average particle size is 10 μm or less, the proportion of primary particles is 50% or more, and the purity is 99.99. A step of forming 9% or more of Mo powder into a disk-shaped formed body, a step of sintering the formed body at 1000 ° C. or higher and 1500 ° C. or lower , and a hot working of the sintered body at 700 ° C. or higher and 1200 ° C. or lower. And a step of subjecting the sintered body to a recrystallization heat treatment at 1000 ° C. or higher and 1300 ° C. or lower .
The second Mo sputtering target is produced by a method of producing a purity of 99.9% or more, an average crystal grain size of 60 μm or less, an average Vickers hardness Hv of the sputtering surface of 150 to 200, and a variation of the Vickers hardness Hv within ± 10%. The sputtering surface is a method of manufacturing a Mo sputtering target in which crystals having an aspect ratio of 3 or less are 70% or more in area ratio, and a step of EB melting Mo powder or Mo block having a purity of 99.9% or more, and an ingot the is characterized in that it comprises a step of hot working at 700 ° C. or higher 1200 ° C. or less, a step of recrystallizing heat treatment of the ingot at 1000 ° C. or higher 1300 ° C. or less, the.
Further, the third method for producing the Mo sputtering target has a purity of 99.9% or more, an average crystal grain size of 60 μm or less, an average Vickers hardness Hv of the sputtering surface of 150 to 200, and a variation of the Vickers hardness Hv within ± 10%. The sputtering surface is a method for producing a Mo sputtering target in which crystals with an aspect ratio of 3 or less are 70% or more in area ratio, and the average particle size is 10 μm or less, the proportion of primary particles is 50% or more, and the purity is 99.9% or more. A Mo sintered body sintered at 1000 ° C. or higher and 1500 ° C. or lower, or an ingot containing EB-melted Mo powder or Mo block body having a purity of 99.9% or higher sealed in an iron or stainless steel capsule from to, the step of hot working at 700 ° C. or higher 1200 ° C. or less, Engineering recrystallization heat treatment at 1000 ° C. or higher 1300 ° C. or less , It is characterized in that it comprises a.
Any of the manufacturing methods is effective for a target whose diameter is increased to 320 mm or more.

Since the Mo sputtering target of the present invention reduces variations in Vickers hardness on the sputtering surface, a uniform structure is obtained. Further, the crystal orientation of the sputter surface is random orientation. For this reason, the sputtering rate is stabilized and the life of the target can be extended.
Moreover, the manufacturing method of the Mo sputtering target of this invention can obtain the Mo sputtering target which has a uniform structure | tissue or random orientation efficiently. In particular, even when the target size is increased, a uniform structure or a randomly oriented Mo sputtering target can be obtained.

The figure which shows the measurement position of the Vickers hardness of the sputter | spatter surface of Mo sputtering target.

The Mo sputtering target of the present invention is an Mo sputtering target having a purity of 99.9% or more, an average crystal grain size of 60 μm or less, and an average Vickers hardness H of the sputtering surface.
It is characterized in that v is 150 to 200 and the variation in Vickers hardness Hv is within ± 10%.
First, the purity of Mo is 99.9 wt% or more (3N or more). The higher the Mo purity, the better 9
It is preferably 9.99 wt% or more (4 N or more), more preferably 99.999 wt% (5 N or more).
The purity is measured by removing metal components (oxygen, nitrogen, carbon), and metallic impurities Na, K, M
The value obtained by subtracting the total value of g, Fe, Cu, Cr, Al, Ca, Ni, W, U, and Th from 100% is the purity of Mo. Also, oxygen is 100 ppm or less, nitrogen is 30 ppm or less, carbon 1
It is preferably 0 ppm or less. In the present invention, ppm is w unless otherwise specified.
It means tppm.

The average particle size is 60 μm or less. When the average grain size of the Mo crystal exceeds 60 μm, the structure becomes too large and the variation in Vickers hardness is increased. The average particle size is preferably 30μ
m or less.
The line intercept method is used to obtain the average particle diameter. An arbitrary sputter surface (unit area 500 μm × 500 μm) of the Mo sputtering target is taken on an enlarged photograph (such as an optical microscope photograph), and the number of Mo crystal particles existing on a straight line 500 μm is counted. (500μ
m / number of Mo crystal particles on a straight line of 500 μm) = average value, this operation is performed three times, and the average value is defined as “average particle diameter”.

Further, the average Vickers hardness Hv of the sputtering surface is 150 to 200, and the variation of the Vickers hardness Hv is within ± 10%. FIG. 1 is a diagram showing measurement points of the Vickers hardness of the sputter surface. The central part (position 1) of the disk-shaped target, the positions near the outer periphery (positions 2 to 9) on the four straight lines that pass through the central part and the circumference is equally divided, and the positions (positions) that are ½ the distance 10 to 17) are the measurement points. When you can measure the sputter surface as it is,
The measurement is performed as it is, and when measurement is difficult, a 10 mm square sample including the sputter surface may be cut out and measured. The position near the outer periphery is assumed to be 90% when the distance from the center to the outer periphery is 100%. The measurement of Vickers hardness is performed using a Vickers hardness tester under the conditions of a load of 200 g and a load application time of 15 seconds.
The average value of the measurement results at 17 points is taken as the average value of Vickers hardness Hv. Also, the variation is
[(Vickers hardness of measurement point−average value) / average value] × 100%.
First, the average Vickers hardness Hv of the sputtering surface is 150 to 200. If the Vickers hardness Hv is less than 150, the hardness of the target is insufficient. Possible causes of insufficient hardness include a case where pores (pores) are present inside the target and a case where a soft impurity metal such as Fe is segregated.

On the other hand, when the Vickers hardness exceeds 200, there may be mentioned a case where a long and thin fibrous structure having an aspect ratio of 5 or more is provided. For this reason, in this invention, it is preferable not to comprise the fibrous structure. If there is a fibrous structure, the crystal grain existence ratio (grain boundary existence ratio) can vary, making it difficult to reduce the Vickers hardness variation to 10% or less.
Further, the variation in Vickers hardness Hv is in the range of ± 10%. In the present invention, a uniform structure is obtained by controlling the variation in hardness. This is because the ratio of the partial Mo crystal grains and grain boundaries is made substantially uniform by controlling the average grain size.
In order to obtain such a uniform structure, it is preferable that crystals having an aspect ratio of 3 or less are 70% or more in terms of area ratio on the sputtering surface. If the Mo crystal grains have an aspect ratio of 3 or less, there is no significant difference in the number of Mo crystal grains per unit area of 100 μm × 100 μm, so that variation in hardness can be suppressed.
Further, a recrystallized structure is preferable in order to suppress variation in Vickers hardness within ± 10%. In the case of the recrystallized structure, the average particle size is reduced to 60 μm or less, and further to 30 μm or less, and the fibrous structure is eliminated, so that crystals having an aspect ratio of 3 or less can be made 70% or more in area ratio.

In addition, it is possible to obtain a sputtering target having a long life and high long-term reliability by reducing the change in the sputtering rate. For this reason, even if the thickness of the sputtering target is increased to 6 mm or more, it can be used sufficiently.
Further, as a method for reducing the change in the sputtering rate, the crystal orientation of the sputter surface can be changed to random orientation. Random orientation indicates a state where there is no orientation of 50% or more in a specific crystal orientation. Crystal orientation can be measured by X-ray diffraction (XRD). X-ray diffraction is performed with a Cu target (Cu-Kα), a tube voltage of 40 kV, and a tube current of 100 mA.
In addition, (110), (200), (211), (
310) The relative intensity of the peaks on each surface is (110)>(211)> ((200) or (3
It is preferable to decrease in the order of 10)). The X-ray diffraction intensities of (200) and (310) are
Since (200) and (310) may be large, they may show almost the same value. Therefore, (110)>(211)> (200) ≧ (310) or (110)> (211
)> (310) ≧ (200).

In addition, when an arbitrary sample was cut out from the Mo sputtering target and the X-ray diffraction of the sputtering surface was performed, the relative intensity of the peaks on each surface of the X-ray diffraction was determined by the order of the peak height of the sputtering surface and the PDF peak (powder When the order of the height of the XRD peak of the sample is compared, it becomes almost the same. The ratio of the heights of the individual peaks may differ between the sputter surface and the PDF (powder), but the order of the detected peak heights is almost the same. The peak order of the sputtering surface is (110)> (2
11)> ((200) or (310)), and the fact that this order is the same even when the powder (PDF peak) is obtained indicates that the target has a uniform random orientation over the entire target.

A stable sputter rate can be obtained by adjusting either the Vickers hardness or the crystal orientation after adjusting the average particle diameter, but a more stable sputter rate can be obtained by controlling both the Vickers hardness and the crystal orientation. can get.
Further, by controlling the Vickers hardness or the crystal orientation, a stable sputtering rate can be obtained even if a large target having a diameter of 320 mm or more is obtained, so that long-term reliability is improved.
The relative density is preferably 99.5% or more. The relative density is determined by dividing the actual measurement value measured by the Archimedes method with the theoretical density of molybdenum being 10.22 g / cm ³ . Specifically, (actual measured value by Archimedes method / theoretical density 10.22) × 100 (%) =
Relative density.

Next, a manufacturing method will be described. Although the manufacturing method of Mo sputtering target of this invention is not specifically limited, The following are mentioned as a method obtained efficiently.
The production method of the first Mo sputtering target of the present invention has an average particle size of 10 μm or less,
A step of forming Mo powder having a primary particle ratio of 50% or more and a purity of 99.9% or more into a disk-shaped formed body, a step of sintering the formed body at 1000 ° C. or higher, and a sintered body at 700 ° C. It comprises a step of hot working at the above temperature and a step of recrystallizing the sintered body at 700 ° C. or higher.

The first production method is characterized in that Mo powder having an average particle size of 10 μm or less and a primary particle ratio of 50% or more and a purity of 99.9% or more is used as a raw material powder.
In order to control the Vickers hardness, it is necessary to control the average grain size of the Mo crystal. The average particle diameter of the Mo powder is preferably 10 μm or less. If the average particle size exceeds 10 μm, the average particle size (average crystal particle size) of the target may exceed 60 μm when grain growth occurs after sintering.
Moreover, it is preferable that the ratio of a primary particle is 50% or more. When Mo powder containing a large amount of secondary particles in which particles are bonded to each other is used, the proportion of Mo crystals may be partially biased and the Vickers hardness variation may exceed 10%. The production method of Mo powder with 50% or more primary particles is a method of sufficiently pulverizing and sieving the Mo powder, or as described in Japanese Patent Application No. 2009-163106, the inner wall is formed by Mo in the process of producing Mo powder. As a drying step (a step of preparing molybdenum oxide powder by drying the second aqueous solution containing the molybdenum compound), the second aqueous solution is sprayed onto the rotating plate, and the molybdenum compound rotates. There is a step of drying with a spray dryer while dropping the plate. Refer to Japanese Patent Application No. 2009-163106 for the manufacturing method of Mo powder with a high ratio of primary particles.

Next, the process which shape | molds Mo powder to a disk-shaped molded object is performed. A known forming method such as mold molding can be applied to the molded body, and it is also effective to cover the inner wall with Mo in order to prevent contamination of the mold impurities. In the case of mold molding, a large target having a diameter of 320 mm or more or a thickness of 6 mm or more can be produced by increasing the mold size.
Next, the process of sintering a molded object at 1000 degreeC or more is performed. The sintering method is hot press or H
IP etc. can be applied. Moreover, the method of multi-stage sintering combining atmospheric pressure sintering, hot press, or HIP is mentioned. The sintering temperature depends on the pressure applied during sintering, but is 1000 to 150.
A range of 0 ° C. is preferred. If the temperature exceeds 1500 ° C., the grain growth of Mo crystals is promoted, and it becomes difficult to make the average grain size of Mo crystal grains 60 μm or less. The pressure is 500 atm (50M
Pa) or more is preferable.

Next, the process which hot-processes the obtained Mo sintered compact at 700 degreeC or more is performed. Hot working includes hot forging, hot extrusion, hot rolling, and the like. If the hot working temperature is less than 700 ° C., working strain tends to remain. The upper limit of the hot working temperature is not particularly limited, but is preferably 1200 ° C. or lower in consideration of the load on the apparatus. Further, the processing rate is arbitrary, and is appropriately selected from the Mo sintered body and the desired target size.
Next, the obtained Mo sintered body is subjected to a recrystallization heat treatment at 700 ° C. or higher. In the sintered body after the sintering process, Mo crystals grow to some extent. When the grains are growing, the ratio of the Mo crystals present varies, and the Vickers hardness and crystal orientation vary. For this reason, a method of making the structure more uniform by recrystallization is effective. For complete recrystallization, the recrystallization heat treatment temperature is preferably set to 1000 ° C. or higher and 1300 ° C. or lower. Especially the diameter is 320
This temperature is effective for a large target having a thickness of mm or more or a thickness of 6 mm or more.
After the recrystallization heat treatment, surface processing and backing plate bonding are performed as necessary.

The manufacturing method of the second Mo sputtering target according to the present invention has a purity of 99.9% or more.
o The step of EB melting the powder or Mo block body, the step of hot working the ingot at a temperature of 700 ° C. or higher, and the step of recrystallizing the ingot at 700 ° C. or higher. is there.
First, in the second production method, Mo powder or Mo block having a purity of 99.9% or more is converted into EB.
A process of dissolving is performed. Mo block body is a compact of Mo powder, a sintered body of Mo powder, Mo
One of the melting ingots.
Either the Mo powder or the Mo block body is EB-melted (electron beam melting) to produce an ingot. By EB dissolution, impurities in the Mo powder or the Mo block body can be further reduced. Moreover, the ingot which once reset the dispersion | variation in Mo crystal size of Mo powder or a Mo block body can be manufactured. For this reason, Mo purity 9
It is suitable for obtaining a higher-purity Mo sputtering target of 9.99 wt% or more.
Next, a step of hot working the obtained Mo ingot at 700 ° C. or higher is performed. Hot working includes hot forging, hot extrusion, hot rolling, and the like. If the hot working temperature is less than 700 ° C., working strain tends to remain. The upper limit of the hot working temperature is not particularly limited, but is preferably 1200 ° C. or lower in consideration of the load on the apparatus. Further, the processing rate is arbitrary, and is appropriately selected from the Mo ingot and the desired target size.

Next, a step of subjecting the obtained ingot to recrystallization heat treatment at 700 ° C. or higher is performed. By recrystallization, the structure can be made more uniform.
Similar to the first manufacturing method, after recrystallization, surface processing and bonding of the backing plate are performed as necessary.

The third Mo sputtering target production method of the present invention is a step of sealing a Mo sintered body or ingot in an iron or stainless steel capsule and then hot working at 700 ° C. or higher, and recrystallizing at 700 ° C. or higher. And a step of heat treatment.
First, after a Mo sintered body or ingot is sealed in an iron or stainless steel capsule, a hot working process is performed at 700 ° C. or higher. The Mo sintered body manufactured by the sintering method or the Mo ingot manufactured by the melting method is sealed in an iron or stainless steel capsule. By sealing the capsule, it is possible to prevent external impurities and surface oxidation.
Iron or stainless steel capsules are softer than Mo and do not interfere with hot working. Then, hot working is performed at 700 ° C. or higher. Hot working includes plastic working such as hot forging, hot rolling, hot extrusion, etc., target size preparation, average grain size (average crystal grain size),
It is effective for controlling the crystal orientation.
Next, a recrystallization heat treatment step is performed at 700 ° C. or higher. By recrystallization, the average grain size of the Mo crystal can be further refined. After recrystallization, surface processing and backing plate bonding are performed as necessary.

In the third production method, it is preferable to use the first production method as the method for obtaining the Mo sintered body and the second production method as the method for obtaining the Mo ingot. When the third manufacturing method is applied after using the sintered body of the first manufacturing method or the ingot of the second manufacturing method, the variation in Vickers hardness can be controlled within ± 5%.
If it is the above manufacturing methods, Vickers hardness and crystal orientation can be controlled after reducing the average grain size of Mo crystals. For this reason, a large target having a target diameter of 320 mm or more and a thickness of 6 mm or more can be produced.

[Example]
Example 1
Mo powder having an average particle size of 10 μm, a primary particle ratio of 60%, and a purity of 99.99% was prepared. Using this Mo powder, a cylindrical shaped body was manufactured, 1200 ° C., pressure 1100 atm,
HIP sintering was performed in 5 hours. Then, hot working (rolling after heating at 1100 ° C. × 1 hour) was performed at 1200 ° C. × 3 hours.
Surface polishing was performed to obtain a Mo sputtering target having a diameter of 350 mm and a thickness of 10 mm, and then a backing plate was joined. The relative density of the Mo target is 99.8%.
Met.
(Example 2)
An average particle size of 10 μm, a primary particle ratio of 50%, and a purity of 99.99% Mo powder was sintered to obtain a sintered body (Mo block body), and then EB melted to produce a Mo ingot. The Mo ingot was subjected to hot working (rolling and forging) at 1150 ° C. and recrystallization heat treatment at 1000 ° C. for 5 hours to obtain a cylindrical Mo target. Surface polishing is performed, diameter 300mm x thickness 10m
After obtaining m Mo sputtering target, the backing plate was joined. M
o When the purity was measured, the purity was as high as 99.995 wt% or more. The relative density of the Mo target was 99.9%.
(Example 3)
An Mo powder having an average particle size of 7 μm, a primary particle ratio of 70%, and a purity of 99.99% was prepared.
Using this Mo powder, a cylindrical molded body was manufactured, and hot press sintering was performed at 1200 ° C. and a pressure of 600 atm for 6 hours. Next, the Mo sintered body was covered with a stainless steel capsule.
Thereafter, the shape was adjusted by a hot forging process at 850 to 1150 ° C. and a hot rolling process at 850 to 1150 ° C. The stainless capsule was removed and recrystallization heat treatment was performed at 1100 ° C. By performing surface polishing, a Mo sputtering target having a diameter of 400 mm and a thickness of 8 mm was manufactured. Thereafter, the backing plate was joined. The relative density of the Mo target was 99.9%.

(Comparative Example 1)
Mo powder having an average particle size of 5 μm, a primary particle ratio of 40%, and a purity of 99.99% was prepared. Using this Mo powder, a disk-shaped molded body was manufactured, and 1250 ° C., 1000 atm, 2 hours of H
IP treatment was performed. The HIP sintered body was hot worked at 550 ° C. to adjust the shape. Then 55
Recrystallization heat treatment was performed at 0 ° C.
Then, surface processing was performed and the Mo sputtering target of diameter 300mm x thickness 8mm was manufactured. Next, the backing plate was joined. The relative density of the obtained Mo target was 99.8%.
For the Mo sputtering targets of Examples 1 to 3 and Comparative Example 1, the average particle size of Mo crystals, the ratio (area%) of the aspect ratio of 3 or less, the average value and the variation of Vickers hardness were measured. The results are shown below.
The measurement of Mo crystal is performed in a unit area of 500 μm × 500 in an arbitrary cross section parallel to the sputtering surface
An enlarged photograph of μm was taken and the line intercept method was used. The ratio (area%) of Mo crystals having an aspect ratio of 3 or less was determined from the same enlarged photograph.
Further, for Vickers hardness, 17 samples of 5 mm square shown in FIG. 1 were cut out, and a Vickers hardness tester was used under the conditions of a load of 200 g and a load application time of 15 seconds.

As can be seen from the table, in the Mo targets according to Examples 1 to 3, the average value of the Vickers hardness Hv was in the range of 150 to 200, and the variation thereof was also within 10%. Further, as a result of observing the structure, a fibrous structure having an aspect ratio of 5 or more was not observed.
On the other hand, the thing of the comparative example 1 had Vickers hardness Hv exceeding 200, and the dispersion | variation exceeded 10%. As a result of observing the structure, a fibrous structure having an aspect ratio of 5 or more was observed with an area ratio of 5%.
Next, X-ray diffraction analysis was performed on the sputtering surfaces of the sputtering targets of Examples 1 to 3 and Comparative Example 1 to confirm the orientation. X-ray diffraction shows copper target (Cu-Kα), tube voltage 4
The test was performed at 0 kV and a tube current of 100 mA. (110), (200), (211), (310)
The order of relative intensity ratios was examined. In X-ray diffraction, analysis was performed using 17 sputter surfaces of samples used for measurement of Vickers hardness (analysis was performed before forming an indentation for measuring Vickers hardness). The results are shown in Table 2.

As can be seen from the table, in the sputtering targets according to Examples 1 to 3, the order of X-ray diffraction intensities is (110)>(211)>(200)> (310) or (110)> (211).
>(310)> (200). All showed random orientation. On the other hand, the thing of the comparative example 1 had the location which shows a partially different orientation.
Table 3 shows the results of pulverizing each sample into powder and analyzing the X-ray diffraction of the powder.

In the Mo sputtering target according to the example, the order of the intensity of the X-ray diffraction on the sputtering surface and the order of the intensity of the powder were the same. For this reason, it turns out that the random orientation is maintained throughout the target which concerns on an Example.
On the other hand, the thing of the comparative example had a different location by a place (sample). This means that there is a portion where the crystal orientation is different as it goes in the thickness direction of the target.
Next, sputtering was performed using the Mo sputtering target according to Examples 1 to 3 and Comparative Example 1 to perform a Mo film forming step. As a result, when the Mo sputtering target according to Examples 1 to 3 was used, the change in the film formation amount per unit time was within 5% until the end. On the other hand, the thing of the comparative example 1 had the time slot | zone which changes 10%. For this reason, it can be seen that the sputtering rate of the comparative example 1 is greatly changed.
The Mo sputtering target according to the present example has a stable sputtering rate and can perform film formation with high long-term reliability.

(Examples 4 to 6)
Mo powder having an average particle diameter of 10 μm, a primary particle ratio of 80%, and a purity of 99.99% was prepared.
Using this Mo powder, a sputtering target according to Examples 4 to 6 was manufactured in a manufacturing process shown in Table 4 after being formed into a disk shape. The same measurement as in Example 1 was performed for each target.
The results are shown below.

The Mo sputtering targets according to Examples 4 to 6 were examined for the average grain size of Mo crystals, the ratio of the aspect ratio of 3 or less, and the Vickers hardness (average value, variation) of the sputtering surface.

Next, X-ray diffraction was performed on the sample on the sputtered surface, and the order of intensity was examined.

All showed the same order when the intensity ratios of the sputtering surface and the PDF were compared. Therefore, it can be seen that the random orientation is maintained not only on the sputtering surface but also inside the target.
When sputtering was performed using these targets, the change in the film formation amount per unit time was within 5% until the end. For this reason, it turned out that the stable sputtering rate can be maintained to the last.

1 ... Sputtering surface of sputtering target

Claims (10)

In a Mo sputtering target with a purity of 99.9% or more,
The average crystal grain size is 60 μm or less, the average Vickers hardness Hv of the sputtered surface is 150 to 200, the variation of the Vickers hardness Hv is within ± 10% , and the sputtered surface has a crystal with an aspect ratio of 3 or less and the area ratio is 70% or more. Mo sputtering target characterized by this.   The Mo sputtering target according to claim 1, wherein the Mo sputtering target does not have a fibrous structure. The Mo sputtering target according to claim 1 or 2 , wherein the diameter is 320 mm or more. The Mo sputtering target according to any one of claims 1 to 3 , wherein the Mo sputtering target has a recrystallized structure. When the X-ray diffraction of the sputtered surface is performed, the relative intensity of the peaks of each surface of (110), (200), (211), (310) is (110)>(211)> ((200) or (310) The Mo sputtering target according to any one of claims 1 to 4 , wherein the Mo sputtering target decreases in the order of)). In a Mo sputtering target with a purity of 99.9% or more,
When the average crystal grain size is 60 μm or less and the X-ray diffraction of the sputtered surface is performed, the relative intensity of the peaks of each surface of (110), (200), (211), (310) is (110)> (211) > Mo sputtering target characterized by decreasing in the order of ((200) or (310)). Purity 99.9% or more, average grain size 60 μm or less, spatter surface average Vickers hardness Hv is 150 to 200, Vickers hardness Hv variation is within ± 10%, and sputter surface has an aspect ratio of 3 or less crystal And a manufacturing method of a Mo sputtering target which is 70% or more,
A step of forming Mo powder having an average particle diameter of 10 μm or less and a primary particle ratio of 50% or more and a purity of 99.9% or more into a disk-shaped molded body;
Sintering the molded body at 1000 ° C. or higher and 1500 ° C. or lower ;
A step of hot working the sintered body at 700 ° C. or higher and 1200 ° C. or lower ;
A step of subjecting the sintered body to recrystallization heat treatment at 1000 ° C. or higher and 1300 ° C. or lower ,
The manufacturing method of Mo sputtering target characterized by comprising. Purity 99.9% or more, average grain size 60 μm or less, spatter surface average Vickers hardness Hv is 150 to 200, Vickers hardness Hv variation is within ± 10%, and sputter surface has an aspect ratio of 3 or less crystal And a manufacturing method of a Mo sputtering target which is 70% or more,
EB dissolution of Mo powder or Mo block having a purity of 99.9% or more,
Hot working the ingot at 700 ° C. or more and 1200 ° C. or less ;
A step of recrystallizing the ingot at 1000 ° C. or higher and 1300 ° C. or lower ,
The manufacturing method of Mo sputtering target characterized by comprising. Purity 99.9% or more, average grain size 60 μm or less, spatter surface average Vickers hardness Hv is 150 to 200, Vickers hardness Hv variation is within ± 10%, and sputter surface has an aspect ratio of 3 or less crystal And a manufacturing method of a Mo sputtering target which is 70% or more,
Mo sintered body obtained by molding Mo powder having an average particle size of 10 μm or less, a primary particle ratio of 50% or more, and a purity of 99.9% or more, and sintering at 1000 ° C. or more and 1500 ° C. or less, or a purity of 99.9% or more A process of hot working at 700 ° C. or more and 1200 ° C. or less after sealing an ingot obtained by EB-dissolving Mo powder or Mo block body in an iron or stainless steel capsule,
Recrystallization heat treatment at 1000 ° C. or higher and 1300 ° C. or lower ,
The manufacturing method of Mo sputtering target characterized by comprising. The diameter of a target is 320 mm or more, The manufacturing method of the Mo sputtering target of any one of Claim 7 , Claim 8 and Claim 9 characterized by the above-mentioned.

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