TW201636444A - Ruthenium-based target and intermediate layer for magnetic recording media - Google Patents

Abstract

Provided is a ruthenium-based target, comprising a base phase of ruthenium and an amorphous phase of a first oxide selected from the group consisting of: MgB4O7, Mg2B2O5, Mg3B2O6, and any combination thereof. An intermediate layer sputtered from the ruthenium-based target is also provided for magnetic recording media. Since a recording layer formed on the intermediate layer has been proved to have an excellent crystalline orientation texture, the magnetocrystalline anisotropy and coercivity of the recording layer are improved, and the signal to noise ratio and the areal recording density of the magnetic recording media are also increased. Accordingly, the demands of high-density magnetic recording media are met.

Description

Thiol-based target and interlayer film for magnetic recording medium

The present invention relates to a ruthenium-based target and an intermediate film for a magnetic recording medium.

a ruthenium-based alloy or pure ruthenium containing at least one of cobalt, chromium, titanium, niobium, tantalum, tungsten, copper, magnesium, zirconium, manganese, lanthanum, aluminum, iron, molybdenum, and boron, and further containing oxidizing At least one of cerium (SiO ₂ ), titanium oxide (TiO ₂ ), cobalt monoxide (CoO), cobalt dioxide (CoO ₂ ), tungsten dioxide (WO ₂ ), and tantalum pentoxide (Ta ₂ O ₅ ) Ruthenium-based materials composed of oxides are often used as intermediate films in vertical magnetic recording media to assist in crystallographically oriented microstructure of magnetic grains of a recording film of a vertical magnetic recording medium. Orientation texture) and controlling the grain size of the magnetic crystal grains, thereby increasing the magnetic coercivity (Hc) and magnetocrystalline anisotropy (Ku) of the recording film, decoupling the magnetic exchange of the recording film The uniformity improvement and the bit error ratio (BER) are lowered, and the signal to noise ratio (SNR) and the areal recording density of the magnetic recording medium are improved.

However, for the recording film, the space for the oriented structure, the magnetocrystalline anisotropy, and the magnetic coercivity which are obtained by the interlayer film formed of the ruthenium-based material containing the foregoing oxide are still insufficient, and thus it is not in conformity with the current Requirements for high density magnetic recording media.

In view of the above disadvantages of the prior art, the object of the present invention is to effectively assist the crystal orientation structure of the recording film, thereby improving the magnetic crystal anisotropy performance and magnetic coercivity of the recording film, and improving the signal-to-noise ratio and surface recording of the magnetic recording medium. Density, which in turn meets the needs of high density magnetic recording media.

In order to achieve the foregoing object, one of the technical means adopted by the present invention is to provide a ruthenium-based target comprising: a base phase containing ruthenium; and an amorphous phase containing a first oxide, the first The monooxide is selected from the group consisting of MgB ₄ O ₇ , Mg ₂ B ₂ O ₅ , Mg ₃ B ₂ O _{6 ,} and combinations thereof.

After the ruthenium-based target is subjected to a high-temperature vacuum heat-pressing process, an amorphous phase composed of MgB ₄ O ₇ , Mg ₂ B ₂ O ₅ , Mg ₃ B ₂ O ₆ or a combination thereof is uniformly distributed in the base phase and It is small and has good high temperature stability. It can prevent the occurrence of arcing during sputtering and improve the stability of sputtering and the yield of products.

Preferably, the first oxide of the ruthenium-based target is present in an amount of from 0.1 mole percent to 9 mole percent of the overall ruthenium base target. Preferably, the first oxide of the ruthenium-based target is present in an amount from 1 mole percent to 8 mole percent of the overall ruthenium base target. More preferably, the first oxide of the ruthenium-based target is present in an amount from 3 moles to 6 mole percent of the overall ruthenium-based target.

Preferably, the base phase of the ruthenium-based target comprises at least one selected from the group consisting of cobalt, chromium, titanium, niobium, tantalum, tungsten, copper, magnesium, zirconium, manganese, lanthanum, aluminum, iron, molybdenum and boron. The elements in the group formed. More preferably, the base phase of the ruthenium based target comprises cobalt or chromium or titanium. More preferably, the base phase comprises a samarium cobalt alloy, a samarium cobalt chrome alloy or a ruthenium chrome alloy or a niobium titanium alloy.

Preferably, the content of the elements contained in the base phase of the ruthenium-based target is from 10 mole percent to 70 mole percent of the total ruthenium base target.

Preferably, the ruthenium-based target further comprises a second oxide, the second oxide comprising at least one selected from the group consisting of niobium, titanium, chromium, tungsten, aluminum, gallium, magnesium, molybdenum, manganese, An element of a group consisting of cerium, zirconium, iron, zinc, and cerium.

Preferably, the second oxide of the ruthenium based target comprises from 1.5 mole percent to 24 mole percent of the overall ruthenium based target. Preferably, the second oxide of the ruthenium based target comprises from 8 mole percent to 24 mole percent of the overall ruthenium based target.

Also in order to achieve the foregoing object, another technical means adopted by the present invention is to provide an intermediate film for a magnetic recording medium comprising: a base phase containing germanium; and an amorphous phase including one The first oxide is selected from the group consisting of MgB ₄ O ₇ , Mg ₂ B ₂ O ₅ , Mg ₃ B ₂ O _{6 ,} and combinations thereof.

By the amorphous phase composed of MgB ₄ O ₇ , Mg ₂ B ₂ O ₅ , Mg ₃ B ₂ O ₆ or a combination thereof, the grain properties of the ruthenium base phase of the intermediate film are appropriately coated, The intermediate film can provide a superior crystal orientation effect to the recording film formed on the intermediate film, so that the recording film crystal orientation structure, magnetic crystal anisotropy performance and magnetic coercivity are good, and can be optimized by The signal-to-noise ratio and the surface recording density of the magnetic recording medium produced by the interlayer film and the recording film.

Preferably, the content of the first oxide of the intermediate film is from 0.1 mole percent (mol. percentage) to 9 mole percent of the overall ruthenium base target. Preferably, the first oxide of the ruthenium-based target is present in an amount from 1 mole to 8 moles of the total ruthenium-based target. More preferably, the content of the first oxide of the intermediate film is from 3 mole percent to 6 mole percent of the overall interlayer film. Thereby, the amorphous item of the intermediate film can have more excellent high wettability, so that the intermediate film can have a better crystal orientation structure to more effectively assist the magnetic grain of the recording film of the vertical magnetic recording medium. The crystal orientation structure improves the magnetic crystal anisotropy performance and magnetic coercivity of the recording film, and improves the signal-to-noise ratio and surface recording density of the magnetic recording medium.

Preferably, the base phase of the ruthenium-based target comprises at least one selected from the group consisting of cobalt, chromium, titanium, niobium, tantalum, tungsten, copper, magnesium, zirconium, manganese, lanthanum, aluminum, iron, molybdenum and boron. The elements in the group formed. More preferably, the base phase of the interlayer film comprises cobalt or chromium or titanium. More preferably, the base phase comprises a samarium cobalt alloy, a samarium cobalt chromium alloy or a niobium chromium alloy or a niobium titanium alloy.

Preferably, the content of the elements contained in the base phase of the ruthenium-based target is from 10 mole percent to 70 mole percent of the total ruthenium base target.

Preferably, the intermediate film further comprises a second oxide, the second oxide comprising at least one selected from the group consisting of niobium, titanium, chromium, tungsten, aluminum, gallium, magnesium, molybdenum, manganese, niobium, An element of a group consisting of zirconium, iron, zinc, and antimony. By the addition of the second oxide, it is possible to provide a crystal grain oriented structure required for the recording film.

Preferably, the second oxide of the interlayer film comprises from 1.5 mole percent to 24 mole percent of the overall ruthenium based target. More preferably, the second oxide of the interlayer film comprises from 8 mole percent to 24 mole percent of the overall ruthenium based target.

Preferably, the intermediate film is made of the ruthenium-based target through a sputtering process. Optional sputtering processes such as, but not limited to, magnetron sputtering processes, electronic plasma processes, and ion beam sputtering processes.

Accordingly, the interlayer film has high sputter stability and yield during sputtering, and has MgB ₄ O ₇ , Mg ₂ B ₂ O ₅ , Mg ₃ B ₂ O ₆ or a combination thereof. The amorphous phase formed can provide a more superior crystal orientation effect to the recording film formed on the intermediate film, and enhance the crystal orientation structure, magnetocrystalline anisotropy performance and magnetic coercivity of the recording film, so that The magnetic recording medium produced by the interlayer film and the recording film can have a signal-to-noise ratio and a surface recording density which meet the requirements of a high-density magnetic recording medium.

In the following, embodiments of the present invention will be described in detail by the following specific embodiments, and those skilled in the art can readily understand the advantages and functions of the present invention, and without departing from the invention. Various modifications and changes are made in the spirit of the invention to practice or apply the invention.

Example 1 to 6 : Preparation and analysis of ruthenium-based targets

The preparation of the ruthenium-based targets of Examples 1 to 6 was as follows: A metal powder was mixed with a first oxide and ball-milled to obtain a mixed powder. Then, the mixed powder was subjected to hydrogen reduction at a temperature of 650 ° C and a pressure of 760 bar for 2 hours to obtain a reduced powder. Next, the reduced powder is ground in a high speed grinder for 2 hours to 4 hours, uniformly filled in a graphite mold and applied to a hydraulic press at a pressure of 300 psi to form a Early embryo. The priming embryo was placed in a hot press furnace together with the graphite mold, and sintered at a sintering temperature of 1000 ° C to 1200 ° C and a sintering pressure of 422 bar for 3 hours to obtain a sulfhydryl group of each example. Target.

The components of the metal powder of Examples 1 to 6, the composition of the first oxide, the molar ratio of the metal powder to the first oxide, the grinding time of the reduced powder, the sintering temperature of the blast, and the sintering time of the blast In Table 1.

The preparation of the ruthenium-based targets of Examples 2 to 5 and Examples 1 and 6 is different as follows: In Examples 2 to 5, the metal powder and the first oxide system are further mixed with a second oxide. Next, Examples 2 to 5 obtained the mixed metal powder, the first oxide and the second oxide by ball milling to obtain the mixed powder of Examples 2 to 5.

The components of the second oxide of Examples 2 to 5 and the metal powder, the molar ratio of the first oxide to the second oxide are shown in Table 2.

The components of the ruthenium-based targets of Examples 1 to 6 were analyzed by an inductively coupled plasma spectrometer (ICP), brand: Perkin Elmer, model: 5300 DV, and the results of the analysis are shown in Table 3.

Referring to Figures 1 to 6, the analysis of Examples 1 to 6 was carried out using a scanning electron microscopy (SEM, brand: Hitachi, model: 3400N, accelerating voltage: 15 kV, working distance: 3 cm). A metallographic diagram obtained from a base target. It can be observed from FIGS. 1 to 6 that the ruthenium-based target of each embodiment mainly contains a light-colored phase and a dark-colored phase, and is shown in Table 4, and an Energy Dispersive Spectrometer (EDS) result is obtained. It was confirmed that the pale phase of each example was a base containing ruthenium composed of the metal powder of each example; the dark phase of Examples 1 and 6 was composed of the first oxides of Examples 1 and 6, respectively. The first oxide phase; the dark phase of Examples 2 to 5 is a second oxide phase composed of the first oxide phase and the second oxide composed of the first oxides of Examples 2 to 5 composition.

Referring to Figs. 1 to 6, the phenomenon in which the magnesium atom or the boron atom was solid-solved was not observed in the ruthenium-containing base phase of each of the examples. As shown in Table 4, by the EDS analysis, no magnesium atom or boron atom was detected in the base phase (light phase) containing ruthenium, and it was confirmed that the ruthenium-based target of each example contained a good high-temperature stability. A mono-oxide phase, and the first oxide phase does not cause solid solution with the ruthenium-containing base phase. Furthermore, it can be observed from FIGS. 1 to 6 that the dark phase of each embodiment has a uniform distribution in the light phase and is fine, so that the ruthenium-based target of each embodiment can be prevented from arcing during sputtering. In turn, the stability of the sputtering and the yield of the sputtered interlayer film are improved.

X-ray diffractometer (XRD), label: Rigaku, model: Ultima IV, scanning with Kα ray of Cu at a speed of 6 degrees per minute from 2θ=20 degrees to 2θ=80 degrees The X-ray diffraction spectra of the ruthenium-based targets of Examples 1 and 4 to 6 were measured, and the X-ray diffraction spectra of the respective examples were compared with the joint committee of powder diffraction standard (JCPDS). The diffraction diffracted data (PDF) was compared. The X-ray diffraction spectra and alignment results of Examples 1 and 4 to 6 are shown in FIGS. 7 to 12.

7 to 12, the characteristic peaks of the X-ray diffraction spectrum of the ruthenium-based target of Examples 1-5 are not the X-ray diffraction spectrum of the Mg ₂ B ₂ O ₅ crystal (No. 86-0531). The characteristic peaks were matched, and the characteristic peak of the X-ray diffraction spectrum of the ruthenium-based target of Example 6 did not match the characteristic peak of the X-ray diffraction spectrum (No. 31-0787) of the MgB ₄ O ₇ crystal. The characteristic peaks of the X-ray diffraction spectrum of the ruthenium-based targets of Examples 1 and 6 matched the characteristic peaks of the X-ray diffraction spectrum (No. 70-0274) of the ruthenium crystal, and the ruthenium groups of Examples 2 to 5 The characteristic peak of a part of the characteristic peak of the X-ray diffraction spectrum of the target and the X-ray diffraction spectrum of the ytterbium crystal (No. 70-0274), the characteristic peak of the X-ray diffraction spectrum of the chromium crystal (No. 88-2323), and cobalt The characteristic peaks of the X-ray diffraction spectrum (No. 15-0806) of the crystal match. Further, according to the results of FIGS. 1 to 6 and the aforementioned EDS analysis, the ruthenium base materials of Examples 1 to 6 comprise a base phase composed of ruthenium or osmium, cobalt and chromium, and Mg ₂ B ₂ O ₅ or MgB ₄ O _{7 .} The first oxide phase is formed. It can be seen from this that the crystal structure of Mg ₂ B ₂ O ₅ or MgB ₄ O ₇ in the ruthenium-based targets of Examples 1 to 6 after sintering is amorphous, that is, after sintering, Examples 1 to 6 The first oxide phase of the ruthenium based target is an amorphous phase. Therefore, the ruthenium-based targets of Examples 1 to 6 contain a base phase composed of ruthenium or osmium, cobalt and chromium, and an amorphous phase composed of Mg ₂ B ₂ O ₅ or MgB ₄ O ₇ .

Comparative example 1 : Existing bismuth-based targets and examples 1 and 6 Comparison of bismuth-based targets

In this comparative example, a conventional ruthenium-based target was compared with the ruthenium-based targets of Examples 1 and 6. The conventional ruthenium-based target of the comparative example was made of ruthenium and boron trioxide (B ₂ O ₃ ). 92.50: 7.50 molar ratio made.

13 to 15 are the through-type electrons of the interlayer film of the ruthenium-based target of Example 1, the ruthenium-based target of Example 6, and the conventional ruthenium-based target of the comparative example which were individually sputter-sputtered. Microscope (TEM) image. The intermediate film formed by sputtering of the conventional ruthenium-based target of the comparative example comprises a base phase 10 composed of ruthenium and a boron trioxide phase 11 composed of boron trioxide.

As can be seen from Figs. 13 to 15, Examples 1 and 6 are compared with the lattice arrangement in the respective crystal grains 100 of the base phase 10 of the interlayer film which is separately sputter-plated by the prior art bismuth-based target of the comparative example. The lattice arrangement in the crystal grains 200, 300 of the base phases 20, 30 of the intermediate film obtained by the ruthenium-based target is relatively order, so the intermediate film prepared by the ruthenium-based targets of Examples 1 and 6 The crystallinity of the base phase 20, 300 is obviously better than the base phase 10 of the intermediate film which is separately sputtered from the prior art ruthenium base of the comparative example.

As shown in FIGS. 13 and 14, the amorphous phases 21, 31 composed of Mg ₂ B ₂ O ₅ or MgB ₄ O ₇ are located between two adjacent crystal grains 200, 300 of the base phases 20, 30, that is, at two The grain boundaries of the adjacent crystal grains 200 and 300 and the grain boundary of each of the crystal grains 200 and 300 are relatively obvious. It is understood that the amorphous phases 21 and 31 completely cover the respective crystal grains 200 and 300 of the base phases 20 and 30, It can be confirmed that the amorphous phase 21, 31 composed of Mg ₂ B ₂ O ₅ or MgB ₄ O ₇ is the base phase 20, 30 of the intermediate film which can be obtained by the ruthenium-based targets of Examples 1 and 6. The crystal grains 200, 300 are distributed independently of each other in the intermediate film. As shown in FIG. 15, in contrast to the intermediate film made of the conventional ruthenium-based target of the comparative example, although the boron trioxide phase 11 is an amorphous phase, the wettability of the boron trioxide phase 11 is excellent. The intermediate film made of the conventional ruthenium-based target of the comparative example is more uneven than the intermediate film obtained by the ruthenium-based target of Examples 1 and 6, except that the grain distribution of the base phase 10 is relatively uneven. The standard deviation of the average grain size of phase 10 is also large.

Further, a gas flow rate of 50 standard milliliters per minute (sccm) was used on the intermediate film made of the conventional ruthenium-based target of the comparative example and the ruthenium-based target of Examples 1 and 6 (using Sputtering a target of the same cobalt-platinum alloy target (CoPtX, X=Cr, B, Mo, Ti, Si under argon), 20 mTorr (mTorr) gas pressure and 200 W (W) sputtering power The recording film composed of Ta, Ru) was analyzed by TEM. Referring to FIGS. 16 to 18, the ruthenium-based targets formed in Examples 1 and 6 are compared with the grain distribution of the recording film formed on the interlayer film made of the conventional ruthenium-based target of the comparative example. The grain distribution of the recording film on the interlayer film prepared by the material is obviously uniform; as shown in Table 5, the grain size of the recording film on the interlayer film obtained by the ruthenium-based targets of Examples 1 and 6 The standard deviations were 0.69 nm and 1.05 nm, respectively, which were apparently lower than the 2.90 nm of the recording film formed on the interlayer film made of the conventional ruthenium-based target of this comparative example.

The recording film on the interlayer film prepared based on the intermediate film formed of the conventional ruthenium base material of the comparative example and the ruthenium base target of Examples 1 and 6 is the same as the same cobalt chrome platinum alloy target According to the results of the sputtering process, it can be confirmed from the results of FIGS. 16 to 18 and Table 5 that the intermediate film made of the conventional ruthenium-based target of the comparative example contains the base phase composed of ruthenium and An intermediate film made of the ruthenium-based target of Example 1 or 6 in an amorphous phase composed of Mg ₂ B ₂ O ₅ or MgB ₄ O ₇ can provide a more excellent crystal orientation effect to the recording film, and The crystal orientation structure, the magnetocrystalline anisotropy performance and the magnetic coercivity of the recording film are effectively improved, thereby improving the signal-to-noise ratio and the surface recording density of the magnetic recording medium, thereby achieving the requirement of a high-density magnetic recording medium.

Comparative example 2 : Existing bismuth-based targets and examples 1 and 6 Comparison of bismuth-based targets

In the comparative example, a conventional ruthenium-based target was compared with the ruthenium-based targets of Examples 1 and 6. The conventional ruthenium-based target of the comparative example was made of ruthenium and tantalum pentoxide (Ta ₂ O ₅ ). Made with a molar ratio of 95.00:5.00.

Fig. 19 is a transmission electron microscope (TEM) image of an intermediate film formed by sputtering of the conventional ruthenium-based target of this comparative example. The intermediate film formed by sputtering of the prior art ruthenium-based target of the comparative example comprises a base phase 40 composed of tantalum and a tantalum pentoxide phase 41 composed of tantalum pentoxide.

As can be seen from Figures 13, 14 and 19, Example 1 is compared to the lattice arrangement in the respective crystal grains 400 of the base phase 40 of the intermediate film which is separately sputtered by the prior art bismuth-based target of the comparative example. And the lattice arrangement in the crystal grains 200 and 300 of the base phases 20 and 30 of the interlayer film prepared by the ruthenium-based target of 6 is relatively order, so that the ruthenium-based targets of Examples 1 and 6 are obtained. The crystallinity of the base phases 20, 30 of the interlayer film is preferably better than the base phase 40 of the interlayer film which is separately sputtered from the prior art ruthenium base of the comparative example.

As shown in FIG. 19, the intermediate film made of the conventional ruthenium-based target of the comparative example has a ruthenium pentoxide phase 41 between two adjacent crystal grains 400 of the base phase 40, that is, located in two adjacent crystal grains. On the grain boundary of 400. As shown in FIGS. 13 , 14 and 19 , the intermediate film made of the conventional ruthenium-based target of the comparative example is compared with the intermediate film prepared by the ruthenium-based target of Examples 1 and 6, and the comparative example can be seen. The intermediate film made of the conventional ruthenium-based target has a larger standard deviation of the average grain size of the base phase 40 except that the grain distribution of the base phase 40 is relatively uneven.

A recording film composed of a cobalt-chromium-platinum alloy target was sputter-sputtered by an intermediate film made of the conventional ruthenium-based target of the comparative example, and analyzed by TEM; wherein the existing ruthenium-based target of the comparative example was formed. The cobalt chrome-platinum alloy target used in the recording film on the prepared intermediate film and the process parameters were the same as those of the recording film formed on the intermediate film made of the conventional ruthenium-based target of Comparative Example 1, and were also formed in the same manner. The recording film on the interlayer film prepared by the ruthenium base materials of Examples 1 and 6.

Referring to FIGS. 16, 17, and 20, the ruthenium-based target materials formed in Examples 1 and 6 are formed in comparison with the recording film formed on the interlayer film made of the conventional ruthenium-based target of the comparative example. The grain distribution of the recording film on the obtained intermediate film was apparently uniform; as shown in Table 5, the standard deviation of the grain size of the recording film on the interlayer film obtained by the ruthenium-based targets of Examples 1 and 6 It was 0.69 nm and 1.05 nm, which was apparently lower than 1.33 nm of the recording film formed on the interlayer film made of the conventional ruthenium base target of this comparative example.

The recording film on the interlayer film prepared based on the intermediate film formed of the conventional ruthenium base material of the comparative example and the ruthenium base target of Examples 1 and 6 is made of the same cobalt chrome platinum alloy target. The same sputtering process is used, and it can be confirmed from the results of Figs. 16, 17, and 20 and Table 5 that the intermediate film made of the conventional ruthenium-based target of the comparative example contains a base composed of ruthenium. An intermediate film made of the ruthenium-based target of Example 1 or 6 which is composed of an amorphous phase composed of Mg ₂ B ₂ O ₅ or MgB ₄ O ₇ can provide a more excellent crystal orientation effect to the recording film. , the crystal orientation structure, the magnetocrystalline anisotropy performance and the magnetic coercivity of the recording film can be effectively improved, thereby improving the signal-to-noise ratio and the surface recording density of the magnetic recording medium, thereby achieving the requirements of the high-density magnetic recording medium.

Comparative example 3 : Existing bismuth-based targets and examples 1 and 6 Comparison of bismuth-based targets

In this comparative example, a conventional ruthenium-based target was compared with the ruthenium-based targets of Examples 1 and 6. The conventional ruthenium-based target of the comparative example was made of ruthenium, cobalt, chromium and titanium dioxide (TiO ₂ ) at 25.00. : 61.00: 6.00: 8.00 molar ratio made.

Fig. 21 is a transmission electron microscope (TEM) image of an intermediate film of the conventional ruthenium-based target of this comparative example which was sputter-plated. The intermediate film formed by sputtering of the prior art ruthenium-based target of the comparative example comprises a base phase 50 composed of ruthenium, cobalt and chromium and a titania phase 51 composed of titanium dioxide.

As can be seen from Figures 13, 14 and 21, Example 1 is compared to the lattice arrangement in the respective crystal grains 500 of the base phase 50 of the intermediate film which is separately sputtered by the prior art bismuth-based target of the comparative example. And the lattice arrangement in the crystal grains 200 and 300 of the base phases 20 and 30 of the interlayer film prepared by the ruthenium-based target of 6 is relatively order, so that the ruthenium-based targets of Examples 1 and 6 are obtained. The crystallinity of the base phases 20, 30 of the interlayer film is obviously better than the base phase 50 of the interlayer film formed by sputtering of the conventional ruthenium-based target of the comparative example. As shown in FIG. 19, in the intermediate film made of the conventional ruthenium-based target of the comparative example, the titania phase 51 is located between two adjacent crystal grains 500 of the base phase 50, that is, the crystals located in the two adjacent crystal grains 500. In the world. Referring to FIGS. 13 , 14 and 21 , the comparative example is obtained by comparing the intermediate film made of the conventional ruthenium-based target of the comparative example with the intermediate film prepared by the ruthenium-based target of Examples 1 and 6. The intermediate film made of the conventional ruthenium-based target has a larger standard deviation of the average grain size of the base phase 50 except that the grain distribution of the base phase 50 is relatively uneven.

A recording film composed of a cobalt-chromium-platinum alloy target was sputter-sputtered by an intermediate film made of the conventional ruthenium-based target of the comparative example, and analyzed by TEM; wherein the existing ruthenium-based target of the comparative example was formed. The cobalt chrome-platinum alloy target used in the recording film on the prepared intermediate film and the process parameters were the same as those of the recording film formed on the intermediate film made of the conventional ruthenium-based target of Comparative Example 1, and were also formed in the same manner. The recording film on the interlayer film prepared by the ruthenium base materials of Examples 1 and 6.

Referring to FIGS. 16, 17, and 22, the ruthenium-based target materials formed in Examples 1 and 6 are formed in comparison with the recording film formed on the interlayer film made of the conventional ruthenium-based target of the comparative example. The grain distribution of the recording film on the obtained intermediate film was apparently uniform; as shown in Table 5, the standard deviation of the grain size of the recording film on the interlayer film obtained by the ruthenium-based targets of Examples 1 and 6 It was 0.69 nm and 1.05 nm, which was apparently lower than 2.52 nm of the recording film formed on the interlayer film made of the conventional ruthenium base target of this comparative example.

The recording film on the interlayer film prepared based on the intermediate film formed of the conventional ruthenium base material of the comparative example and the ruthenium base target of Examples 1 and 6 is made of the same cobalt chrome platinum alloy target. The same sputtering process is used, and it can be confirmed from the results of FIGS. 16, 17, and 22 to and Table 5 that the intermediate film made of the conventional ruthenium-based target of the comparative example includes the ruthenium. An intermediate film made of the base phase and the ruthenium target of Example 1 or 6 composed of an amorphous phase composed of Mg ₂ B ₂ O ₅ or MgB ₄ O ₇ can provide a more excellent crystal orientation effect for recording The film can effectively improve the crystal orientation structure, magnetic crystal anisotropy performance and magnetic coercivity of the recording film, thereby improving the signal-to-noise ratio and the surface recording density of the magnetic recording medium, thereby achieving the requirements of a high-density magnetic recording medium.

In summary, it was confirmed by experimental results that the amorphous phase system composed of MgB ₄ O ₇ or Mg ₂ B ₂ O ₅ was uniformly distributed after the high temperature vacuum heat-pressing process of the ruthenium-based targets of Examples 1 to 6 The small and medium-sized phase prevents arcing during sputtering and improves the stability of the sputtering and the yield of the product. Further, the intermediate film for the magnetic recording medium made of the ruthenium-based target of Examples 1 to 6 is also formed of an amorphous phase consisting of MgB ₄ O ₇ or Mg ₂ B ₂ O ₅ and containing ruthenium. The crystal grains of the base phase can provide a superior crystal orientation effect to the recording film formed on the intermediate film, so that the recording film has a good crystal orientation structure, magnetic crystal anisotropy performance and magnetic coercivity, thereby improving magnetic The recording medium has a signal-to-noise ratio and a surface recording density, and thus meets the requirements of a high-density magnetic recording medium.

Table 1 The composition of the metal powder of each example, the composition of the first oxide, the molar ratio of the metal powder and the first oxide, and the process parameters

Table 2 Metal powders of Examples 2 to 5, components of the first oxide and the second oxide, and molar ratio

Table 3 Inductively coupled plasma spectrometer composition analysis of each example

Table 4 Energy dispersive element analysis spectrometer analysis results of each example

Table 5 Average grain size and standard deviation of the recording film formed on the interlayer film of the targets of Examples 1, 6 and Comparative Examples 1 to 3

10, 20, 30, 40, 50‧ ‧ base phase
100, 200, 300, 400, 500‧‧‧ grains
11‧‧‧Diboron phase
21, 31‧‧‧Amorphous phase
41‧‧‧ bismuth pentoxide
51‧‧‧ Titanium dioxide phase

1 is a metallographic diagram obtained by analyzing a ruthenium-based target of Example 1 by a scanning electron microscope; FIG. 2 is a metallographic diagram obtained by analyzing a ruthenium-based target of Example 2 by a scanning electron microscope; The metallographic pattern obtained by analyzing the ruthenium-based target of Example 3 by a scanning electron microscope; FIG. 4 is a metallographic diagram obtained by analyzing the ruthenium-based target of Example 4 by a scanning electron microscope; The metallographic pattern obtained by analyzing the ruthenium-based target of Example 5 by a scanning electron microscope; FIG. 6 is a metallographic diagram obtained by analyzing the ruthenium-based target of Example 6 by a scanning electron microscope; X-ray diffraction spectrum of the ruthenium-based target; FIG. 8 is an X-ray diffraction spectrum of the ruthenium-based target of Example 2; FIG. 9 is an X-ray diffraction spectrum of the ruthenium-based target of Example 3. Figure 10 is an X-ray diffraction spectrum of the ruthenium-based target of Example 4; Figure 11 is an X-ray diffraction spectrum of the ruthenium-based target of Example 5; Figure 12 is a ruthenium-based target of Example 6. X-ray diffraction spectrum; Figure 13 is a transmission electron microscope image of the interlayer film obtained by sputtering of the ruthenium-based target of Example 1. Figure 14 is a transmission electron microscope image of the interlayer film obtained by sputtering of the ruthenium-based target of Example 6; Figure 15 is a conventional ruthenium-based target of Comparative Example 1 (钌: boron trioxide is 92.50) Mohr: 7.50 mole) Transmissive electron microscope image of the interlayer film obtained by sputtering; FIG. 16 is a penetration of the recording film formed on the interlayer film obtained by sputtering of the ruthenium-based target of Example 1. FIG. 17 is a transmission electron microscope image of a recording film formed on the interlayer film obtained by sputtering on the ruthenium-based target of Example 6; FIG. 18 is an existing 形成 formed in Comparative Example 1. A transmissive electron microscope image of a recording film on an intermediate film obtained by sputtering on a base target; FIG. 19 is a conventional ruthenium-based target of Comparative Example 2 (钌: bismuth pentoxide is 95.00 mol: 5.00 mol a transmission electron microscope image of the intermediate film obtained by sputtering; FIG. 20 is a transmission electron microscope image of the recording film formed on the interlayer film obtained by sputtering of the conventional ruthenium-based target of Comparative Example 2. 21 is a conventional ruthenium-based target of Comparative Example 3 (钌:cobalt:chromium:titanium dioxide) 25.00 Moule: 61.00 Mo Er: 6.00 Mo Er: 8.00 Mohr) Transmissive electron microscope image of the intermediate film obtained by sputtering; FIG. 22 shows that the conventional ruthenium base formed in Comparative Example 3 was sputtered. A transmission electron microscope image of the recording film on the intermediate film.

Claims (11)

A ruthenium-based target comprising: a base phase comprising ruthenium; and an amorphous phase comprising a first oxide selected from the group consisting of MgB ₄ O ₇ and Mg ₂ B ₂ O ₅ , a group of Mg ₃ B ₂ O ₆ and combinations thereof. The ruthenium-based target of claim 1, wherein the first oxide is present in an amount from 0.1 mole percent to 9 mole percent of the overall ruthenium base target. The ruthenium-based target according to claim 1 or 2, wherein the base phase further comprises at least one selected from the group consisting of cobalt, chromium, titanium, niobium, tantalum, tungsten, copper, magnesium, zirconium, manganese, lanthanum, aluminum, An element in a group of iron, molybdenum and boron. The ruthenium-based target according to claim 1 or 2, comprising a second oxide comprising at least one selected from the group consisting of ruthenium, titanium, chromium, tungsten, aluminum, gallium, magnesium, and molybdenum An element of a group consisting of manganese, cerium, zirconium, iron, zinc and cerium. The ruthenium-based target of claim 4, wherein the second oxide comprises from 1.5 mole percent to 24 mole percent of the overall ruthenium base target. An interlayer film for a magnetic recording medium, comprising: a base phase containing ruthenium; and an amorphous phase comprising a first oxide selected from the group consisting of MgB ₄ O ₇ , Mg A group consisting of ₂ B ₂ O ₅ , Mg ₃ B ₂ O ₆ and combinations thereof. The intermediate film for a magnetic recording medium according to claim 6, which is made of the ruthenium-based target according to any one of claims 1 to 5. The intermediate film for a magnetic recording medium according to claim 6 or 7, wherein the content of the first oxide is from 0.1 mol% to 9 mol% of the intermediate film for the magnetic recording medium as a whole. The intermediate film for a magnetic recording medium according to claim 6 or 7, wherein the base phase comprises at least one selected from the group consisting of cobalt, chromium, titanium, lanthanum, cerium, tungsten, copper, magnesium, zirconium, manganese, lanthanum An element of a group consisting of aluminum, iron, molybdenum and boron. The interlayer film for a magnetic recording medium according to claim 6 or 7, further comprising a second oxide different from the first oxide, the second oxide system comprising at least one selected from the group consisting of An element of a group consisting of titanium, chromium, tungsten, aluminum, gallium, magnesium, molybdenum, manganese, cerium, zirconium, iron, zinc, and cerium. The intermediate film for a magnetic recording medium according to claim 10, wherein the second oxide accounts for 1.5 mol% to 24 mol% of the intermediate film for the magnetic recording medium as a whole.