TWI834072B - Ru-al alloy target and method of preparing the same - Google Patents

Abstract

Provided is a Ru-Al alloy target, which includes ruthenium, aluminum and an oxide. Based on a total atom number of the Ru-Al alloy target, a content of aluminum is 5 at% to 50 at% and a content of the oxide is 5 at% to 40 at%; meanwhile, a content of chlorine of the Ru-Al alloy target is less than 50 ppm; in a XRD pattern of a longitudinal section of the Ru-Al alloy target, a ratio of an intensity of (110) crystal plane of RuAl phase to an intensity of (111) crystal plane of Al phase is more than 2. The Ru-Al alloy target has not only elevated bending strength and relative density but also better resistance to oxidation.

Description

Ruthenium aluminum alloy target material and its preparation method

The present invention relates to a ruthenium-aluminum alloy target material and a manufacturing method thereof, in particular, to a ruthenium-aluminum alloy target material and a manufacturing method thereof that can be used to make the base layer of a heat-assisted magnetic recording medium.

Due to the increasing demand for information storage capacity in the market, perpendicular magnetic recording (PMR) media with higher magnetic recording density has been increasingly used in recent years to further increase the storage capacity of hard disks. However, in order to further increase the magnetic recording density, the current perpendicular magnetic recording media still needs to be improved in terms of thermal stability, writability, signal to noise ratio (SNR), etc., and a thermally assisted magnetic recording medium is currently being developed. Recording technology (Heat-Assisted Magnetic Recording, HAMR) to achieve the purpose of increasing storage capacity.

Generally speaking, the layered structure of a heat-assisted magnetic recording medium can include a substrate, an adhesion layer, a soft under layer, a heat sink, and an under layer from bottom to top. ), barrier layer (diffusion barrier), magnetic recording layer (magnetic recording layer) and cap layer (cap layer), etc. Thermal-assisted magnetic recording technology uses a laser beam to accurately focus on the magnetic recording layer and heat it, so that the temperature of the magnetic particles in the magnetic recording bits is higher than the Curie temperature, thereby temporarily reducing the magnetic coercivity to achieve data The purpose of writing.

At present, the recording layer of heat-assisted magnetic recording media usually uses iron-platinum-based materials. In order to ensure the grain orientation, grain size and distribution of the magnetic particles in the magnetic recording layer, a base layer with fine grain and adjustable lattice matching is required. material, and currently the base layer material is usually ruthenium-aluminum alloy. However, the melting point of ruthenium is as high as 2334°C, while the melting point of aluminum is only about 660°C. The melting points of the two metals are too different, making it difficult to obtain high-density targets through sintering. In addition, the aluminum raw materials for making ruthenium-aluminum alloy targets are often The presence of a high content of chlorine can easily generate aluminum chloride. However, aluminum chloride has strong water absorption characteristics. Therefore, if the ruthenium-aluminum alloy target is not stored in an appropriate environment, the surface of the target is prone to oxidation.

In addition, it is known that when an additional oxide is added to the ruthenium-aluminum alloy as a base layer, the grain size of the magnetic particles in the magnetic recording layer can be further adjusted. However, the process of mixing and sintering ruthenium, aluminum and oxide to form a target material Among them, aluminum easily reacts with oxides to form aluminum oxide, which then creates holes, resulting in a low density of ruthenium-aluminum alloy targets containing oxides and poor bending strength.

It can be seen that the current targets composed of ruthenium-aluminum alloys or ruthenium-aluminum alloy targets containing oxides generally have problems such as low density, low flexural strength, and prone to oxidation, which in turn affects the subsequent sputtering process. At the same time, the application of ruthenium-aluminum alloy targets in heat-assisted magnetic recording media is restricted. Therefore, it is necessary to develop new technical solutions to cope with the future development trend of the industry.

In view of the problems faced by the existing technology, the purpose of this creation is to provide a ruthenium-aluminum alloy target material, which not only has higher relative density and flexural strength, but also has better anti-oxidation ability, making the ruthenium-aluminum alloy target provided by this creation Aluminum alloy targets are easy to store and can improve the quality and yield of thin films formed by sputtering, making them suitable as base layer materials and used in heat-assisted magnetic recording media.

In order to achieve the aforementioned purpose, the present invention provides a ruthenium-aluminum alloy target, which includes ruthenium (Ru), aluminum (Al) and an oxide; wherein, based on the total number of atoms of the entire ruthenium-aluminum alloy target, the aluminum content is greater than or equal to 5 atomic percent (atomic percent, at%) and less than or equal to 50 at%, and the content of the oxide is greater than or equal to 5 at% and less than or equal to 40 at%; the ruthenium-aluminum alloy target material The chlorine (Cl) content is less than 50 parts per million (50 ppm), and in the X-ray diffraction pattern of the longitudinal section of the ruthenium-aluminum alloy target, the ruthenium-aluminum phase is at (110) The ratio of the characteristic peak intensity of the crystal plane to the characteristic peak intensity of the aluminum phase at the (111) crystal plane is greater than 2.

By controlling the ruthenium-aluminum alloy target of this invention, it also has the following technical characteristics: (I) the aluminum content is greater than or equal to 5 at% and less than or equal to 50 at%, (II) the oxide content is greater than or equal to 5 at% and Less than or equal to 40 at%, (III) the chlorine content in the ruthenium-aluminum alloy target is less than 50 ppm, and (IV) the characteristic peak intensity of the ruthenium-aluminum phase on the (110) crystal plane and the characteristics of the aluminum phase on the (111) crystal plane The peak intensity ratio is greater than 2. The ruthenium-aluminum alloy target material created in this invention not only has a relative density of more than 97% and a flexural strength of more than 300 million Pascals (MPa), but also has better anti-oxidation ability.

According to this invention, when calculating the intensity ratio of characteristic peaks of different crystal phases on different crystal planes, if there are multiple characteristic peaks, the characteristic peak with the highest intensity will be used for calculation. For example, in the X-ray diffraction pattern of the ruthenium-aluminum alloy target provided by this creation, the ruthenium-aluminum phase has three obvious characteristic peaks on the (110) crystal plane, which are respectively located at 2θ close to 29.73° and close to 42.54 ° and close to 77.85°, and take the characteristic peak with the highest intensity (2θ close to 42.54°) to calculate the characteristic peak intensity ratio.

Preferably, in the X-ray diffraction pattern of the longitudinal section of the ruthenium-aluminum alloy target, the ratio of the characteristic peak intensity of the ruthenium-aluminum phase at the (110) crystal plane to the characteristic peak intensity of the aluminum phase at the (111) crystal plane is greater than 2 and less than 25. More preferably, in the X-ray diffraction pattern of the longitudinal section of the ruthenium-aluminum alloy target, the ratio of the characteristic peak intensity of the ruthenium-aluminum phase at the (110) crystal plane to the characteristic peak intensity of the aluminum phase at the (111) crystal plane is greater than 2 and less than 24.

Preferably, the chlorine content in the ruthenium-aluminum alloy target is less than 45 ppm. More preferably, the chlorine content in the ruthenium-aluminum alloy target is less than or equal to 43 ppm.

In some embodiments of the invention, the chlorine content in the ruthenium-aluminum alloy target is greater than or equal to 0.1 ppm and less than 50 ppm; in other embodiments of the invention, the chlorine content in the ruthenium-aluminum alloy target is It is greater than or equal to 0.1 ppm and less than 45 ppm; in some embodiments of the present invention, the chlorine content in the ruthenium-aluminum alloy target is greater than or equal to 0.1 ppm and less than or equal to 43 ppm.

Preferably, the oxide includes magnesium monoxide (MgO), titanium dioxide (TiO ₂ ), silicon dioxide (SiO ₂ ), chromium trioxide (Cr ₂ O ₃ ), cobalt monoxide (CoO), cobalt tetraoxide (Co ₃ O ₄ ), boron trioxide (B ₂ O ₃ ), ferric oxide (Fe ₂ O ₃ ), silver oxide (Ag ₂ O), copper oxide (CuO), nickel monoxide (NiO), dioxide Tin (SnO ₂ ), magnesium orthotitanate (Mg ₂ TiO ₄ ), phosphorus pentoxide (P ₂ O ₅ ), manganese trioxide (Mn ₂ O ₃ ), vanadium pentoxide (V ₂ O ₅ ), Zirconium dioxide (ZrO ₂ ), tantalum pentoxide (Ta ₂ O ₅ ), strontium monoxide (SrO), hafnium dioxide (HfO ₂ ), niobium pentoxide (Nb ₂ O ₅ ), tungsten trioxide (WO ₃ ) or a combination thereof.

In some embodiments of the present invention, the oxide includes magnesium monoxide, titanium dioxide, silicon dioxide, chromium trioxide, cobalt monoxide, diboron trioxide, ferric oxide, magnesium orthotitanate, and trioxide. Manganese, vanadium pentoxide, zirconium dioxide, tantalum pentoxide, strontium monoxide, niobium pentoxide, tungsten trioxide or combinations thereof.

According to this invention, based on the total number of atoms of the entire ruthenium-aluminum alloy target, the ruthenium content is greater than or equal to 10 at% and less than or equal to 90 at%. Preferably, based on the total number of atoms of the entire ruthenium-aluminum alloy target, the ruthenium content is greater than or equal to 15 at% and less than or equal to 90 at%.

Preferably, the relative density of the ruthenium-aluminum alloy target is above 97%. More preferably, the relative density of the ruthenium-aluminum alloy target is greater than or equal to 97.1% and less than or equal to 99.8%.

Preferably, the flexural strength of the ruthenium-aluminum alloy target is above 300 MPa. More preferably, the flexural strength of the ruthenium-aluminum alloy target is greater than or equal to 300 MPa and less than or equal to 680 MPa.

In addition, the invention also provides a method for making a ruthenium-aluminum alloy target, which includes the following steps: Step (a): Make the ruthenium raw material and the aluminum raw material form a ruthenium-aluminum pre-alloyed raw material, wherein the chlorine content in the aluminum raw material is small. 50 ppm; step (b): mix the ruthenium-aluminum prealloy raw material and an oxide raw material to obtain a raw material mixture; and step (c): sinter the ruthenium-aluminum pre-alloyed raw material at a temperature greater than or equal to 900°C and less than or equal to 1500°C. Raw material mixture to obtain the ruthenium-aluminum alloy target; wherein, based on the total number of atoms of the raw material mixture, the added amount of the aluminum raw material is greater than or equal to 5 at% and less than or equal to 50 at%, and the oxide raw material is The addition amount is greater than or equal to 5 at% and less than or equal to 40 at%; the chlorine content in the ruthenium-aluminum alloy target is less than 50 ppm, and in the X-ray diffraction pattern of the longitudinal section of the ruthenium-aluminum alloy target , the ratio of the characteristic peak intensity of the ruthenium-aluminum phase on the (110) crystal plane to the characteristic peak intensity of the aluminum phase on the (111) crystal plane is greater than 2.

By using (1) controlling the range of addition amounts of aluminum raw materials and oxide raw materials, (2) controlling the range of chlorine content in aluminum raw materials, (3) pre-preparing ruthenium-aluminum pre-alloyed raw materials and ( 4) Technical means such as controlling the sintering temperature range can make the produced ruthenium-aluminum alloy targets have higher relative density and flexural strength, and at the same time also have better oxidation resistance, which can effectively solve the problem of ruthenium-aluminum alloy targets. The surface of the material is easily oxidized and difficult to preserve.

According to this invention, the chlorine content in the ruthenium raw material or oxide raw material is usually less than 50 ppm, while the aluminum raw material usually contains a higher chlorine content. Therefore, by controlling the chlorine content in the aluminum raw material to be less than the aforementioned specific range of 50 ppm, That is, the chlorine content in the produced ruthenium-aluminum alloy target can be effectively controlled to be less than the aforementioned specific range of 50 ppm.

According to the invention, in step (a), the ruthenium raw material and the aluminum raw material can be formed into the ruthenium-aluminum pre-alloyed raw material by vacuum induction melting (VIM) and atomized powder spraying, but it is not limited thereto. Preferably, in step (a), the ruthenium raw material and the aluminum raw material are formed by vacuum induction melting to form the ruthenium-aluminum pre-alloy raw material.

Preferably, in step (a), the ruthenium-aluminum prealloy raw material is further subjected to a heat treatment step at a temperature of 500°C to 700°C. The heat treatment step is to reduce the oxidized substances in the ruthenium-aluminum prealloy raw material. Specifically, in step (a), the ruthenium-aluminum prealloy raw material is placed in a hydrogen environment and heat-treated at a temperature of 500°C to 700°C for 1 hour to 4 hours.

According to the present invention, in step (b), the mixing step can use any method that can uniformly mix the raw materials. For example, the mixing step can achieve the purpose of uniformly mixing the raw materials through ball milling, but is not limited to this.

According to the invention, in step (c), before sintering the raw material mixture, a pre-pressing step can be performed. The pre-pressing step can use any means that can press the raw material mixture into a fixed shape. For example, the prepressing step may be to place the raw material mixture into a hydraulic press at room temperature and perform prepressing at a pressure of approximately 1,000 pounds per square inch (psi) to 2,000 psi. But not limited to this.

According to this creation, based on the total number of atoms of the raw material mixture, the added amount of ruthenium raw material is greater than or equal to 10 at% and less than or equal to 90 at%. Preferably, based on the total number of atoms of the raw material mixture, the added amount of ruthenium raw material is greater than or equal to 15 at% and less than or equal to 90 at%.

Preferably, the oxide raw materials include magnesium monoxide raw materials, titanium dioxide raw materials, silicon dioxide raw materials, chromium oxide raw materials, cobalt monoxide raw materials, cobalt tetroxide raw materials, boron trioxide raw materials, ferric oxide raw materials, and silver oxide. Raw materials, copper oxide raw materials, nickel monoxide raw materials, tin dioxide raw materials, magnesium orthotitanate raw materials, phosphorus pentoxide raw materials, manganese trioxide raw materials, vanadium pentoxide raw materials, zirconium dioxide raw materials, tantalum pentoxide raw materials , strontium monoxide raw materials, hafnium dioxide raw materials, niobium pentoxide raw materials, tungsten trioxide raw materials or combinations thereof.

In some embodiments of the present invention, the oxide raw materials include magnesium monoxide raw materials, titanium dioxide raw materials, silicon dioxide raw materials, chromium oxide raw materials, cobalt monoxide raw materials, boron trioxide raw materials, iron oxide raw materials, Magnesium orthotitanate raw materials, manganese trioxide raw materials, vanadium pentoxide raw materials, zirconium dioxide raw materials, tantalum pentoxide raw materials, strontium monoxide raw materials, niobium pentoxide raw materials, tungsten trioxide raw materials or combinations thereof.

In some embodiments of the invention, the average particle size of the ruthenium raw material is less than 100 microns (μm), the average particle size of the aluminum raw material is less than 150 μm, and the average particle size of the oxide raw material is less than 35 μm. In other embodiments of the invention, the average particle size of the ruthenium raw material is greater than or equal to 5 μm and less than 100 μm, the average particle size of the aluminum raw material is greater than or equal to 1 μm and less than 150 μm, and the oxide raw material The average particle size is greater than or equal to 0.1 μm and less than 35 μm.

Preferably, in step (c), the sintering pressure is greater than or equal to 350 bar and less than or equal to 1800 bar.

According to the invention, the sintering step can be hot pressing (HP), spark plasma sintering (SPS) or hot isostatic pressing (HIP). For example, when HP is used in the sintering step, the sintering temperature can be 1000°C to 1400°C, the sintering pressure can be 350 bar to 400 bar, and the sintering time can be 2 hours to 4 hours, but is not limited thereto; when When the sintering step uses SPS, the sintering temperature can be 900°C to 1400°C, the sintering pressure can be 450 bar to 550 bar, and the sintering time can be 5 minutes to 1 hour, but is not limited to this; when the sintering step uses HIP , its sintering temperature can be 900°C to 1400°C, the sintering pressure can be 1200 bar to 1800 bar, and the sintering time can be 1 hour to 4 hours, but is not limited to this.

The ruthenium-aluminum alloy film produced by sputtering with the ruthenium-aluminum alloy target provided by this invention has the characteristics of grain refinement, and is particularly suitable as the base layer of a heat-assisted magnetic recording medium, thereby having a fine-grain effect.

In this specification, the "relative density" of the target material refers to the percentage of the measured density of the target material relative to the theoretical density of the target material after the measured density of the target material is obtained by Archimedes' method.

In this specification, the "parts per million (ppm)" refers to the weight of the substance as the basis for comparison. For example, "the chlorine content in the ruthenium-aluminum alloy target is less than 50 ppm" means that the chlorine content is less than 50 parts per million based on the total weight of the ruthenium-aluminum alloy target.

In this specification, the range expressed by "a small value to a large value", unless otherwise specified, means that the range is greater than or equal to the small value and less than or equal to the large value. For example: the temperature is 500℃ to 700℃, which means the temperature range is "greater than or equal to 500℃ and less than or equal to 700℃".

In order to verify the influence of the composition of the ruthenium-aluminum alloy target, the chlorine content, and the relationship between the characteristic peak intensity of the ruthenium-aluminum phase in the (110) crystal plane and the characteristic peak intensity of the aluminum phase in the (111) crystal plane, the following is Several ruthenium-aluminum alloy targets are cited as examples to describe the implementation of the invention in detail. Those with ordinary knowledge in the technical field can easily understand the advantages and effects that the invention can achieve through the contents of this description, and do not depart from the Various modifications and changes are made in the spirit of this creation to implement or apply the content of this creation.

Example 1 to 11 :Ruthenium aluminum alloy Target material

According to the composition listed in Table 1, weigh an appropriate amount of ruthenium powder with an average particle size less than 100 μm and aluminum powder with an average particle size less than 150 μm to prepare a ruthenium-aluminum prealloy powder in advance, wherein aluminum is selected for Examples 1 to 11. The chlorine content in the powder was measured through inductively coupled plasma (ICP) analysis, and the chlorine content was found to be 42 ppm, 48 ppm, 15 ppm, 42 ppm, 23 ppm, 26 ppm, and 37 respectively. ppm, 37 ppm, 11 ppm, 42 ppm and 11 ppm; In addition, in Examples 1 to 11, vacuum induction melting was used to produce ruthenium-aluminum pre-alloy powder, wherein the vacuum induction melting was performed at a pressure of 10 ^-7 bar , carried out at a temperature of 1400°C to 1900°C.

Next, the ruthenium-aluminum pre-alloy powder was placed in a hydrogen environment at a temperature of 600°C for heat treatment for 2 hours. Then, place the aforementioned heat-treated ruthenium-aluminum pre-alloy powder and an appropriate amount of oxide powder with an average particle size less than 35 μm in a ball mill, and grind them with a ball-to-material ratio of 1 to 2.5 for 1 hour to 4 hours to mix them evenly. , to obtain a powder mixture.

The powder mixture is placed into a hydraulic press and pre-pressed at a pressure of approximately 1500 psi, and then sintered according to the sintering process and sintering temperature listed in Table 1 below to obtain the ruthenium-aluminum alloy targets of Examples 1 to 11 Among them, if HP is used in the sintering step, the sintering pressure is about 362 bar and the sintering time is 3 hours; if SPS is used in the sintering step, the sintering pressure is about 500 bar and the sintering time is 10 minutes; if HIP is used in the sintering step, The sintering pressure is approximately 1750 bar and the sintering time is 1 hour.

In Table 1 below, the composition of the ruthenium aluminum alloy targets of Examples 1 to 11 can be aRu-bAl-c1MgO-c2TiO ₂ -c3SiO ₂ -c4Cr ₂ O ₃ -c5Mn ₂ O ₃ -c6B ₂ O ₃ -c7Ta ₂ O ₅ -c8CoO-c9Fe ₂ O ₃ -c10V ₂ O ₅ -c11ZrO ₂ -c12WO ₃ -c13Mg ₂ TiO ₄ -c14Nb ₂ O ₅ -c15SrO is shown in the general formula; where a represents the ratio of ruthenium to the ruthenium aluminum alloy target. The content ratio of the total number of atoms, b represents the content ratio of aluminum relative to the total number of atoms of the ruthenium-aluminum alloy target, c1 to c15 represent magnesium monoxide, titanium dioxide, silicon dioxide, chromium trioxide, manganese trioxide, in order. Boron trioxide, tantalum pentoxide, cobalt monoxide, ferric oxide, vanadium pentoxide, zirconium dioxide, tungsten trioxide, magnesium orthotitanate, niobium pentoxide and strontium monoxide relative to ruthenium aluminum alloy The content ratio of the total number of atoms in the target material.

Comparative example 1 to 9 :Ruthenium aluminum alloy target

According to the composition listed in Table 1, weigh appropriate amounts of ruthenium powder with an average particle size less than 100 μm, aluminum powder with an average particle size less than 200 μm, and oxide powder with an average particle size less than 35 μm, and place these powders on In a ball mill, grind it for 1 to 4 hours with a ball-to-material ratio of 1 to 2.5, and mix it evenly to obtain a powder mixture. The chlorine content in the aluminum powder selected for Comparative Examples 1 to 9 is also transmitted through the inductively coupled plasma. The analytical method was used to measure and the chlorine contents were 462 ppm, 462 ppm, 221 ppm, 417 ppm, 583 ppm, 455 ppm, 349 ppm, 266 ppm and 374 ppm respectively. The ruthenium-aluminum alloy targets of Comparative Examples 1 to 9 were then obtained according to the same pre-pressing and sintering processes as in the Examples. The main difference between Comparative Examples 1 to 9 and the Examples is that Comparative Examples 1 to 9 did not simultaneously adopt step three of controlling the chlorine content in the aluminum powder, pre-preparing the ruthenium-aluminum alloy powder, and subjecting the ruthenium-aluminum pre-alloyed powder to heat treatment. or technical means.

The compositions of the ruthenium-aluminum alloy targets of Comparative Examples 1 to 9 and the contents of each component in atomic percentage are listed in Table 1 below. The ruthenium-aluminum alloy targets of Comparative Examples 1 to 9 can also be as described in the previous embodiments. The general formula is expressed, and the content of its components is expressed in the same manner as in the foregoing embodiments.

In this specification, the "content of oxide" refers to the sum of c1 to c15. Table 1: Composition, selected sintering process and sintering temperature of the ruthenium-aluminum alloy targets of Examples 1 to 11 and Comparative Examples 1 to 9 Group Ruthenium aluminum alloy target composition Sintering process Sintering temperature (°C) Example 1 40Ru-40Al-20MgO HP 1400 Example 2 30Ru-50Al-10TiO ₂ -10SiO ₂ HIP 1200 Example 3 55Ru-5Al-20Cr ₂ O ₃ -10Mn ₂ O ₃ -10B ₂ O ₃ SPS 1100 Example 4 55Ru-40Al-5Ta ₂ O ₅ HP 1400 Example 5 80Ru-10Al-5CoO-5Fe ₂ O ₃ HP 1400 Example 6 65Ru-20Al-5V ₂ O ₅ -10ZrO ₂ SPS 1200 Example 7 60Ru-30Al-10WO ₃ SPS 1100 Example 8 65Ru-30Al-5Mg ₂ TiO ₄ HIP 1200 Example 9 80Ru-5Al-10Nb ₂ O ₅ -5SrO HIP 1200 Example 10 10Ru-50Al-20SiO ₂ -10MgO-10Cr ₂ O ₃ HP 1100 Example 11 90Ru-5Al-5TiO ₂ SPS 1200 Comparative example 1 40Ru-40Al-20MgO HP 1400 Comparative example 2 30Ru-50Al-10TiO ₂ -10SiO ₂ HIP 1200 Comparative example 3 55Ru-5Al-20Cr ₂ O ₃ -10Mn ₂ O ₃ -10B ₂ O ₃ SPS 1100 Comparative example 4 55Ru-40Al-5Ta ₂ O ₅ HP 1400 Comparative example 5 35Ru-55Al-10SiO ₂ HP 1200 Comparative example 6 52Ru-45Al-3B ₂ O ₃ HP 1200 Comparative example 7 45Ru-10Al-25TiO ₂ -20Cr ₂ O ₃ SPS 1200 Comparative example 8 76Ru-4Al-10MgO-10ZrO ₂ HP 1300 Comparative example 9 27Ru-30Al-23SiO ₂ -20WO ₃ SPS 1100

analyze 1 :Ruthenium-aluminum phase (110) The characteristic peaks of the crystal plane are related to the aluminum phase. (111) Intensity relationship of characteristic peaks of crystal planes

In this analysis, the ruthenium-aluminum alloy targets of Examples 1 to 11 and Comparative Examples 1 to 9 were selected as the samples to be tested, and the X-ray diffractometer was used to analyze the crystalline form of each sample to be tested to analyze the ruthenium-aluminum phase in (110) The relationship between the characteristic peak intensity of the crystal plane and the characteristic peak intensity of the aluminum phase at the (111) crystal plane.

Specifically, each sample to be tested was first ground in sequence with sandpaper numbers #60, #120, #240, #320, #600, #1000, #1500, #2000, and #4000, and then placed in the XRD machine. The measurement was performed in a scanning range of 2θ from 20° to 80° with a step angle of 0.04°.

The following is explained by taking the results of the ruthenium-aluminum alloy target of Example 1 and Comparative Example 2 as an example. Their respective X-ray diffraction patterns are shown in Figure 1 and Figure 2 respectively, in which each pattern is based on XRD After comparison and identification using the analysis software "jade", the characteristic peaks of different crystals are marked in the XRD pattern.

As can be seen from Figure 1, the ruthenium-aluminum alloy target material of Example 1 has a ruthenium-aluminum phase and an aluminum phase. Among them, the ruthenium-aluminum phase can correspond to three obvious characteristic peaks on the (110) crystal plane, while the aluminum phase can correspond to three obvious characteristic peaks on the (111) crystal plane. ) crystal plane only corresponds to one obvious characteristic peak. It can be seen from this that the ruthenium-aluminum alloy target material of Example 1 contains both the ruthenium-aluminum phase and the aluminum phase.

Looking at Figure 2 again, the ruthenium-aluminum alloy target of Comparative Example 2 has a ruthenium-aluminum phase, an aluminum phase and a ruthenium phase. Among them, the ruthenium-aluminum phase only corresponds to an obvious characteristic peak on the (110) crystal plane, while the aluminum phase has The (111) crystal plane corresponds to four obvious characteristic peaks. It can be seen from this that the ruthenium-aluminum alloy target of Comparative Example 2 has three crystal phases: a ruthenium-aluminum phase, an aluminum phase, and a ruthenium phase. In addition, by comparing the results of Example 1 and Comparative Example 2, it can be seen that in the spectrum of Example 1, the intensity of the characteristic peaks of the ruthenium-aluminum phase at the (110) crystal plane is significantly higher than that of the aluminum phase at the (111) crystal plane. Peak intensity; however, in the spectrum of Comparative Example 2, the relationship between the characteristic peak intensity of the aluminum phase at the (111) crystal plane and the characteristic peak intensity of the ruthenium-aluminum phase at the (110) crystal plane is almost opposite.

In order to quantify the relationship between the intensity of the characteristic peaks of the ruthenium-aluminum phase on the (110) crystal plane and the intensity of the characteristic peaks of the aluminum phase on the (111) crystal plane, this analysis further selects the characteristic peaks with the highest intensity corresponding to the ruthenium-aluminum phase in the spectrum. The characteristic peak of the ruthenium-aluminum phase is used as the molecule, and the characteristic peak with the highest intensity among the characteristic peaks corresponding to the aluminum phase in the spectrum is taken as the denominator. After dividing the two, the intensity of the characteristic peak of the ruthenium-aluminum phase at the (110) crystal plane and the intensity of the aluminum phase are obtained. The ratio of the characteristic peak intensity of the phase in the (111) crystal plane, in order to specifically evaluate the relationship between the two. The results of Examples 1 to 11 and Comparative Examples 1 to 9 are listed in Table 2 below and marked as RuAl/Al values. Taking the results of Example 1 and Comparative Example 2 as an example, in the spectrum of Example 1, the intensity of the strongest characteristic peak corresponding to the ruthenium-aluminum phase (near 2θ is 42.54°) is 552, and the intensity of the strongest characteristic peak corresponding to the aluminum phase (near 2θ is 42.54°) is 552. (38.47°) is 16, so the RuAl/Al value of Example 1 in Table 2 is 12; and in the spectrum of Comparative Example 2, the strongest characteristic peak corresponding to the ruthenium-aluminum phase (close to 2θ is 42.54° ) is 48, and the intensity of the strongest characteristic peak corresponding to the aluminum phase (near 2θ is 38.47°) is 992. Therefore, the RuAl/Al value of Comparative Example 2 in Table 2 is 0.05.

analyze 2 : Chlorine content of target material

The ruthenium-aluminum alloy targets of Examples 1 to 11 and Comparative Examples 1 to 9 were first processed by wire cutting to prepare samples with a size of 2 centimeters (cm) × 2 cm, and then processed by a grinder and using sandpaper number # After using a 240 grinding wheel to remove the line-cut carbonized areas on the surfaces of the samples in each group, a side surface of the target that can be measured for chlorine content was obtained, and then the chlorine content in the samples of Examples 1 to 11 and Comparative Examples 1 to 9 was measured using a glow discharge mass spectrometer. Chlorine content. The chlorine content in the ruthenium-aluminum alloy targets of Examples 1 to 11 and Comparative Examples 1 to 9 is shown in Table 2 below.

analyze 3 : Relative density of target material

The ruthenium-aluminum alloy targets of Examples 1 to 11 and Comparative Examples 1 to 9 were processed by wire cutting and grinding machines to obtain circular targets with an outer diameter of 165 mm and a thickness of 6 mm. According to Germany and France, the relative densities of the ruthenium-aluminum alloy targets of Examples 1 to 11 and Comparative Examples 1 to 9 can be obtained, and the results are recorded in Table 2 below.

analyze 4 : Target flexural strength

First, half of the radius of the ruthenium-aluminum alloy targets of Examples 1 to 11 and Comparative Examples 1 to 9 was processed by wire cutting and grinding to produce a test specimen with a thickness of 3 millimeters (mm), a width of 4 mm, and a length of 25 mm. The pieces were then placed on a universal testing machine for a three-point bending test. The specific steps are to place the test piece on the three-point anti-bending fixture, and use the operating conditions of a span of 20 mm and a pressurization speed of 0.008 mm per second to measure the maximum load before the test piece is bent to break, and then follow the following formula Calculate: flexural strength = (3 × maximum load × span) / (2 × test piece width × test piece thickness × test piece thickness) to obtain the ruthenium-aluminum alloys of Examples 1 to 11 and Comparative Examples 1 to 9 The flexural strength of the target material, and the results are listed in Table 2 below.

analyze 5 : Antioxidant ability of target material

First, the ruthenium-aluminum alloy targets of Examples 1 to 11 and Comparative Examples 1 to 9 were processed by wire cutting to obtain test pieces with a size of 10 mm × 10 mm, and then processed with a grinder and using a grinding wheel with a sandpaper number of #400. After removing the line-cut carbonized area on the surface of each test piece, the test pieces of Examples 1 to 11 and Comparative Examples 1 to 9 were obtained.

Next, the test pieces of Examples 1 to 11 and Comparative Examples 1 to 9 were placed in a high temperature and high humidity oven with a temperature of 45°C and a relative humidity of 90%, and were taken out every hour to examine the oxidation of each group under an optical microscope. situation, until obviously visible oxidation spots appear on the surface of the test piece, record the total time placed in the high-temperature and high-humidity furnace as the time when oxidation spots appear. Here, the results of Example 1 and Comparative Example 5 are used as examples for explanation, which are shown in Figures 3 and 4 respectively. In Figure 3, after the ruthenium-aluminum alloy target specimen of Example 1 was placed in the high-temperature and high-humidity furnace for 61 hours, slightly darker oxidation spots can be observed under an optical microscope; and in Figure 4 , only after placing the ruthenium-aluminum alloy target specimen in Comparative Example 5 in the high-temperature and high-humidity furnace for 5 hours, multiple darker oxidation spots can be clearly observed under an optical microscope. Therefore, it can be understood that the longer the time it takes for oxidation spots to appear after being placed in the high-temperature and high-humidity furnace, it means that the anti-oxidation ability of the aforementioned ruthenium-aluminum alloy target material is better; The shorter the time for oxidation spots to appear, it means that the aforementioned ruthenium-aluminum alloy target has poorer oxidation resistance. The time points at which oxidation spots appear on the ruthenium-aluminum alloy targets of Examples 1 to 11 and Comparative Examples 1 to 9 in high temperature and high humidity environments are listed in Table 2 below. Table 2: Composition, RuAl/Al value, chlorine content, relative density, flexural strength and oxidation spot appearance time of the ruthenium-aluminum alloy targets of Examples 1 to 11 and Comparative Examples 1 to 9 Group Target composition RuAl/Al value Chlorine content (ppm) Flexural strength (MPa) Relative density (%) Time for oxidation spots to appear ( hours ) Example 1 40Ru-40Al-20MgO 12.00 37 342 99.53 61 Example 2 30Ru-50Al-10TiO ₂ -10SiO ₂ 3.19 43 401 99.02 51 Example 3 55Ru-5Al-20Cr ₂ O ₃ -10Mn ₂ O ₃ -10B ₂ O ₃ 20.42 8 329 97.69 106 Example 4 55Ru-40Al-5Ta ₂ O ₅ 5.81 40 488 99.76 52 Example 5 80Ru-10Al-5CoO-5Fe ₂ O ₃ 18.66 15 547 98.31 99 Example 6 65Ru-20Al-5V ₂ O ₅ -10ZrO ₂ 15.34 twenty two 506 98.42 79 Example 7 60Ru-30Al-10WO ₃ 13.25 31 512 99.75 68 Example 8 65Ru-30Al-5Mg ₂ TiO ₄ 9.57 28 630 98.28 76 Example 9 80Ru-5Al-10Nb ₂ O ₅ -5SrO 19.72 4 561 97.34 112 Example 10 10Ru-50Al-20SiO ₂ -10MgO-10Cr ₂ O ₃ 2.63 39 365 98.24 61 Example 11 90Ru-5Al-5TiO ₂ 23.18 3 653 97.17 123 Comparative example 1 40Ru-40Al-20MgO 0.09 131 216 95.14 11 Comparative example 2 30Ru-50Al-10TiO ₂ -10SiO ₂ 0.05 158 265 93.67 8 Comparative example 3 55Ru-5Al-20Cr ₂ O ₃ -10Mn ₂ O ₃ -10B ₂ O ₃ 0.89 45 154 90.18 52 Comparative example 4 55Ru-40Al-5Ta ₂ O ₅ 0.11 119 273 94.43 20 Comparative example 5 35Ru-55Al-10SiO ₂ 0.03 173 198 93.23 5 Comparative example 6 52Ru-45Al-3B ₂ O ₃ 0.08 135 287 91.40 8 Comparative example 7 45Ru-10Al-25TiO ₂ -20Cr ₂ O ₃ 0.41 52 136 92.39 37 Comparative example 8 76Ru-4Al-10MgO-10ZrO ₂ 0.91 37 249 92.66 63 Comparative example 9 27Ru-30Al-23SiO ₂ -20WO ₃ 0.27 97 112 91.17 twenty four

Discussion of experimental results

According to the production process of each embodiment and the results in Table 2, it can be seen that by at least simultaneously using (1) controlling the range of the addition amounts of aluminum raw materials and oxide raw materials, (2) controlling the range of chlorine content in the aluminum raw materials, (3) Technical means such as pre-preparing ruthenium-aluminum pre-alloy raw materials and (4) controlling the sintering temperature range allow the produced ruthenium-aluminum alloy target to have the following technical characteristics at the same time: (I) the aluminum content is greater than or equal to 5 at% and less than or equal to 50 at%, (II) the oxide content is greater than or equal to 5 at% and less than or equal to 40 at%, (III) the chlorine content in the ruthenium-aluminum alloy target is less than 50 ppm, and (IV) the ruthenium-aluminum phase is in ( The ratio of the characteristic peak intensity of the 110) crystal plane to the characteristic peak intensity of the aluminum phase at the (111) crystal plane is greater than 2. Accordingly, the ruthenium-aluminum alloy targets of Examples 1 to 11 not only have a flexural strength of more than 300 MPa and The relative density and other characteristics are more than 97%, and the time point when oxidation spots appear is greater than or equal to 51 hours.

On the other hand, Comparative Examples 1 to 9 do not adopt the aforementioned technical means (1) to (4) at the same time. Therefore, the ruthenium-aluminum alloy targets of Comparative Examples 1 to 9 cannot simultaneously possess the aforementioned technical features (I) to (IV). Not only did the flexural strength of the target material not reach 300 MPa, the highest relative density was only 95.14%, but the time points when oxidation spots appeared were less than or equal to 63 hours, which affected the subsequent sputtering process and the thermally assisted magnetic field. Applications in recording media.

It can be seen that the technical means provided by this creation can achieve high flexural strength and relative density of the ruthenium-aluminum alloy target, and at the same time also have beneficial effects such as better anti-oxidation ability, and thus be suitable for use as heat-assisted magnetic recording. The base layer in the media and be able to meet market needs.

Further refer to the groups of Comparative Examples 1, 2 and 4. The compositions of the ruthenium-aluminum alloy targets in these groups all meet the specific range limited by this invention, and Comparative Example 1 and Example 1, Comparative Example 2 and Example 2 and Comparative Example 4 have the same composition as Example 4. However, since Comparative Examples 1, 2 and 4 did not simultaneously adopt the technical means of (2) and (3) during the production process, resulting in Comparative Examples 1, 2 and 4. 4. The chlorine content of the targets produced is higher than 100 ppm and the RuAl/Al value is lower than 0.12, which are not within the scope of this creation. Accordingly, the ruthenium-aluminum alloy targets of Comparative Examples 1, 2 and 4 The flexural strengths are only 216 MPa, 265 MPa and 273 MPa respectively; the relative densities are only 95.14%, 93.67% and 94.43% respectively; and the appearance time of oxidation spots are 11 hours, 8 hours and 20 hours respectively. It can be seen from this that If the target chlorine content and RuAl/Al value of the ruthenium-aluminum alloy target are not within the range limited by this creation, it will not be able to achieve the effect of increasing the flexural strength and relative density of the target and simultaneously improving the anti-oxidation ability.

Referring further to the group of Comparative Example 3, the composition of the ruthenium-aluminum alloy target material is within the specific range defined by this creation and is the same as the composition of Example 3. However, Comparative Example 3 did not adopt the aforementioned (3) during the production process. Due to the technical means, the RuAl/Al value is only 0.89, which is not within the range of greater than 2 as defined by this creation. Accordingly, the flexural strength of the ruthenium-aluminum alloy target in Comparative Example 3 is only 154 MPa, and the relative density is higher Only 90.18%. It can be seen that even if the RuAl/Al value of the target material is not within the range limited by this creation, it still cannot achieve the effect of improving the flexural strength and relative density of the target material and improving the anti-oxidation ability at the same time. .

Referring further to the group of Comparative Example 8, Comparative Example 8 did not adopt the aforementioned technical means (1) and (3) at the same time during the production process, so that the aluminum content in the target material was 4 at% and the RuAl/Al value was only There are 0.91, which are not within the scope of this creation. According to this, the flexural strength of the ruthenium-aluminum alloy target in Comparative Example 8 is only 249 MPa, and the relative density is only 92.66%. From this, it can be seen that if ruthenium-aluminum The target composition content and RuAl/Al value of the alloy target are not within the scope of this creation, and it is also impossible to achieve the effect of increasing the flexural strength and relative density of the target, and at the same time improving the anti-oxidation ability.

In addition, looking back at the results of Examples 1 to 11, it can be seen that when the oxide content in the ruthenium-aluminum alloy target is appropriately controlled within a specific range of greater than or equal to 5 at% and less than or equal to 40 at%, a variety of different Various types of oxides or their combinations are used as oxides in ruthenium-aluminum alloys. The ruthenium-aluminum alloy targets of these groups can also have the effect of improving the target's flexural strength and relative density, and at the same time improving the anti-oxidation ability.

In summary, this creation controls the aluminum content and oxide content of the ruthenium-aluminum alloy target and the chlorine content in the ruthenium-aluminum alloy target, and simultaneously controls the ruthenium-aluminum phase in the ruthenium-aluminum alloy target (110) The ratio of the characteristic peak intensity of the crystal plane to the characteristic peak intensity of the aluminum phase on the (111) crystal plane can improve the flexural strength and relative density of the ruthenium-aluminum alloy target, and also improve the oxidation resistance of the ruthenium-aluminum alloy target. , and is further suitable for use as the base layer in heat-assisted magnetic recording media. It can also avoid the problem of easy oxidation due to improper storage, further enhancing its commercial value.

without

Figure 1 is an X-ray diffraction pattern of the ruthenium-aluminum alloy target material in Example 1. Figure 2 is an X-ray diffraction pattern of the ruthenium-aluminum alloy target of Comparative Example 2. Figure 3 is an image of the ruthenium-aluminum alloy target in Example 1 after a 61-hour anti-oxidation test and magnified 50 times using an optical microscope. Figure 4 is an image of the ruthenium-aluminum alloy target of Comparative Example 5 after a 5-hour anti-oxidation test and magnified 50 times using an optical microscope.

without.

Claims (10)

A ruthenium-aluminum alloy target material, which contains ruthenium, aluminum and an oxide; wherein, based on the total number of atoms of the entire ruthenium-aluminum alloy target material, the aluminum content is greater than or equal to 5 atomic percent and less than or equal to 50 atomic percent , the content of the oxide is greater than or equal to 5 atomic percent and less than or equal to 40 atomic percent; the chlorine content in the ruthenium-aluminum alloy target is less than 50 parts per million, and in the longitudinal section of the ruthenium-aluminum alloy target In the X-ray diffraction pattern, the ratio of the characteristic peak intensity of the ruthenium-aluminum phase at the (110) crystal plane to the characteristic peak intensity of the aluminum phase at the (111) crystal plane is greater than 2. The ruthenium-aluminum alloy target as claimed in claim 1, wherein in the X-ray diffraction pattern of the longitudinal section of the ruthenium-aluminum alloy target, the characteristic peak intensity of the ruthenium-aluminum phase at the (110) crystal plane is consistent with the aluminum The ratio of the characteristic peak intensities of the phase in the (111) crystal plane is greater than 2 and less than 25. The ruthenium aluminum alloy target as described in claim 1, wherein the oxide includes magnesium monoxide, titanium dioxide, silicon dioxide, chromium trioxide, cobalt monoxide, cobalt tetroxide, boron trioxide, iron oxide, Silver oxide, copper oxide, nickel monoxide, tin dioxide, magnesium orthotitanate, phosphorus pentoxide, manganese trioxide, vanadium pentoxide, zirconium dioxide, tantalum pentoxide, strontium monoxide, hafnium dioxide , niobium pentoxide, tungsten trioxide or combinations thereof. The ruthenium-aluminum alloy target as described in any one of claims 1 to 3, wherein the relative density of the ruthenium-aluminum alloy target is above 97%. The ruthenium-aluminum alloy target material according to any one of claims 1 to 3, wherein the flexural strength of the ruthenium-aluminum alloy target material is above 300 million pascals. A method for manufacturing a ruthenium-aluminum alloy target material, which includes the following steps: Step (a): Make the ruthenium raw material and the aluminum raw material form a ruthenium-aluminum pre-alloy raw material, wherein the chlorine content in the aluminum raw material is less than 50 parts per million; Step (b): Mix the ruthenium-aluminum prealloy raw material and the monooxide raw material to obtain a raw material mixture; and Step (c): sintering the raw material mixture at a temperature greater than or equal to 900°C and less than or equal to 1500°C to obtain the ruthenium-aluminum alloy target; Wherein, based on the total number of atoms of the raw material mixture, the added amount of the aluminum raw material is greater than or equal to 5 atomic percent and less than or equal to 50 atomic percent, and the added amount of the oxide raw material is greater than or equal to 5 atomic percent and less than or equal to 50 atomic percent. Equal to 40 atomic percent; the chlorine content in the ruthenium-aluminum alloy target is less than 50 parts per million, and in the X-ray diffraction pattern of the longitudinal section of the ruthenium-aluminum alloy target, the ruthenium-aluminum phase is in the (110) crystal The ratio of the characteristic peak intensity of the plane to the characteristic peak intensity of the aluminum phase on the (111) crystal plane is greater than 2. The method of claim 6, wherein in step (a), the ruthenium raw material and the aluminum raw material are formed by vacuum induction melting to form the ruthenium-aluminum prealloy raw material. The method of claim 6, wherein in step (a), the ruthenium-aluminum prealloy raw material undergoes a heat treatment step at a temperature of 500°C to 700°C. The production method as described in any one of claims 6 to 8, wherein the oxide raw materials include magnesium monoxide raw materials, titanium dioxide raw materials, silicon dioxide raw materials, chromium trioxide raw materials, cobalt monoxide raw materials, cobalt tetroxide raw materials, trioxide raw materials, Diboron oxide raw materials, ferric oxide raw materials, silver oxide raw materials, copper oxide raw materials, nickel monoxide raw materials, tin dioxide raw materials, magnesium orthotitanate raw materials, phosphorus pentoxide raw materials, manganese trioxide raw materials, dioxide pentoxide Vanadium raw materials, zirconium dioxide raw materials, tantalum pentoxide raw materials, strontium monoxide raw materials, hafnium dioxide raw materials, niobium pentoxide raw materials, tungsten trioxide raw materials or combinations thereof. The preparation method according to any one of claims 6 to 8, wherein in step (c), the sintering pressure is greater than or equal to 350 bar and less than or equal to 1800 bar.