WO1998012698A1

WO1998012698A1 - Magnetic disk medium, magnetic head, magnetic disk apparatus using them, and production method of the disk apparatus

Info

Publication number: WO1998012698A1
Application number: PCT/JP1996/002720
Authority: WO
Inventors: Masatomo Terakado; Akira Ishikawa; Yoshibumi Matsuda; Joe Inagaki; Yotsuo Yahisa; Djuliano Djayaprawira David; Shinji Narishige
Original assignee: Hitachi, Ltd.
Priority date: 1996-09-20
Filing date: 1996-09-20
Publication date: 1998-03-26

Abstract

A method of producing a magnetic recording disk medium, which comprises the step of forming island-like protrusions by sputtering a target consisting principally of an intermetallic compound on a substrate on which a magnetic alloy film is formed. This method can shorten a single processing time, improve thermal stability of the protrusions, and maintain the shape of these protrusions. The resulting magnetic disk medium is not likely to adhere to the head in the case of a narrow head gap. This method can be also applied to the formation of island-like protrusions on the opposed surface of the magnetic head to a slider. A magnetic disk apparatus having a high recording density and reliable lubricity can be obtained by applying the resulting magnetic disk medium or magnetic head.

Description

Specification

Magnetic disk medium, magnetic head, magnetic disk device using the same, and method of manufacturing the same

The present invention relates to a magnetic recording medium such as a magnetic disk medium, a magnetic head, and a magnetic disk device using the same, and more particularly to a magnetic disk device having good sliding reliability and a magnetic disk for realizing the same. Disc media and magnetic heads.

Further, the present invention relates to a method for manufacturing a magnetic disk medium, a magnetic head, and a magnetic storage device using the same. Background art

In recent years, as the size and capacity of magnetic disk drives have been reduced, the recording density of magnetic disk media has been increasing. To increase the recording density of a magnetic disk medium, it is an important requirement to reduce the distance between the magnetic recording film and the magnetic head of the magnetic disk medium. However, if both the magnetic disk medium and the magnetic head have smooth surfaces, the area where they abut during contact start stop (CSS) will have high stiction, and the presence of lubricant Can cause sticking accidents. For this reason, in order to achieve high recording density and high reliability at the same time, it has become necessary to provide a fine surface structure (texture) to the surface of the magnetic disk medium so that it does not easily adhere even at a low flying height. . As a technique for forming a fine texture on the surface of a magnetic disk medium, for example, as described in JP-A-7-254H6, after forming a magnetic recording film so as not to impair the magnetic recording characteristics, protrusions are formed on the protective film using particles as a mask. The configuration that forms Is being planned. It is not clear whether the process can be simplified because a method using particles and a mask as a mask is used.

Japanese Patent Application Laid-Open No. 7-192260 provides a magnetic disk medium having good CSS characteristics by a method of forming a continuous gold urine and film on a glass substrate, fusing the film, and then cooling it to transform the continuous film into a concavo-convex formed product. It is described. According to this method, heating for a long time (3 minutes) is required after forming the metal film, and mass productivity is not clear.

In Japanese Patent Application Laid-Open No. 4-255909, after forming a metal underlayer such as Ti having a low surface energy on a glass substrate, a large amount of coagulation energy such as A1 and a low melting point margin are sputtered to form fine particles. A projection is formed. It is necessary to heat the substrate during or after the deposition of the low-melting-point metal to agglomerate the low-melting-point metal to form a discontinuous projection. In order to improve the magnetic characteristics of the magnetic film formed on the substrate on which the protrusions are formed, the substrate on which the protrusions are formed is heated to an optimum temperature to form a ground film, a magnetic film, and a protective film. There is a need to. At this time, the low melting point metal reacts with or diffuses into the film formed on or in the film. For example, when a magnetic disk medium with a base film, a magnetic film and a protective film formed on the substrate with protrusions made of low-melting point metal and heated to 280 C, the substrate diffuses through the film and becomes magnetic. It is reported to reach the surface of the disk media. (IEEE Transactions on Magnetics, vol.31, No.6, p.2731, 1995)

As described above, when the low-melting point metal such as No. 1 precipitates on the surface of the magnetic disk medium, it is deposited as an impurity on the surface of the magnetic head, and there is a problem that the sliding resistance is deteriorated. Further, low melting point metal such as Ga and In is in a molten state when forming a projection, and as it is, the adhesive strength and strength with a magnetic disk medium are small. For this reason, it is necessary to form a medium film on the substrate, make the low-melting-point metal react with the medium-thinning film, and finally use a complicated fusing to prevent the residual low-melting-point metal from remaining in the molten state. . The present invention has been made in view of the above-mentioned problems of the related art, and is intended to form fine protrusions on the surface of a magnetic disk medium. It is an object of the present invention to provide a magnetic disk medium capable of maintaining its shape after formation.

It is another object of the present invention to provide a magnetic disk medium that satisfies magnetic recording characteristics and sliding reliability.

In addition, fine projections are formed on the surface facing the magnetic disk medium. The thermal stability of the projections is improved, and after the projections are formed, the magnetic head can maintain its shape stably. The purpose is to provide.

In addition, magnetic disk media and magnetic heads suitable for mass production that can easily form magnetic disk media and magnetic heads with a fine texture formed on the surface by shortening the time of one processing The goal is to realize the manufacturing method of It is another object of the present invention to provide a magnetic disk device having excellent magnetic recording characteristics and sliding resistance by using the magnetic disk medium or the magnetic head. Disclosure of the invention

In order to achieve the object of the present invention, a projection is formed by sputtering using a material mainly containing an intermetallic compound as a target. This method does not substantially require post-heating to form protrusions, and is also suitable for forming protrusions on a magnetic recording film.

First, conditions for suppressing the diffusion of the constituent atoms after the formation of the protrusions will be described. First, in order for a projection to be formed, the force of attracting constituent atoms that form the projection must be greater than the force of diffusing to the substrate surface to flatten it. Furthermore, after the projections are formed, the constituent atoms are substantially It must not diffuse and do not substantially react with adjacent layers. From the above, it is preferable that the substance that forms the protrusion is not a single element but a substance in which two or more types of element atoms are bonded to each other. Further, since it is desirable that each constituent atom does not substantially react with an adjacent layer, highly reactive atoms such as alkali metals, alkaline earth metals and halogen elements are excluded from the constituent elements. From the above two-point force, the substance that forms the protrusion is preferably an intermetallic compound. Here, an intermetallic compound is a substance that has a certain dissociation ratio and is composed of two or more types of alkali metals and metal elements other than the above-mentioned metals, and generally has a crystal structure different from that of the constituent elements alone. Have. The use of a metal intermetallic compound is desirable from the viewpoint of suppressing the diffusion of constituent atoms since heating is not required after the formation of the projections.

Next, the process of forming the projections will be described with reference to FIGS. 1, 2, 3, and 4. FIG.

Figure 1 is a part of the Λ-Β equilibrium diagram consisting of A and B atoms. In Fig. 1, the vertical axis represents temperature, and the horizontal axis represents the concentration of B atoms in the AB system. For example, in FIG. 1, at the point X where the concentration of B atoms is xl and 度 1 degree is T1, the crystal phase of Λ atoms and the product phase 0 of the intermetallic compound composed of atoms and B atoms are 0. The fact that each exists at a ratio of b to a indicates that it is energetically stable. This means that the proportion of B atoms to the whole is (a / a + b) X 100%, and the proportion of Λ atoms to the whole is (1-(a / a + b)) X 100 = (b / a + b) X 100%.

In other words, if the concentration of B atoms is xl and the temperature is T 1, and if it is held for a period of time sufficient for diffusion to occur sufficiently, the product phase of A atoms and the crystal phase 金 of the gold S intermetallic compound b Generated at the rate of a. When the concentration of B atoms is X 2 and the temperature is T 1, only crystalline phase 0 of the intermetallic compound can be obtained.

Next, a process of forming a projection will be described with reference to FIGS. 2, 3, and 4. FIG. Figs. 2, 3 and 4 schematically show the process of forming the protrusions. The array or number of children is not necessarily the same as the actual example.

First, as shown in FIGS. 2 and 3, when a target having a composition in which the concentration of B atoms 22 is X1 in FIG. 1 is sputtered, A atoms 21 and B atoms 22 are formed. The particles reach the substrate 101 and combine with each other to form a crystal nucleus 20 of the intermetallic compound Θ. Since A atoms 21 and B atoms 22 are continuously supplied on the substrate 101, the A atoms 21 and B atoms 22 form the crystal nuclei 20 of the intermetallic compound 上の on the substrate 101. Continue to reach places that aren't in one place with the same probability. However, the formation of the crystal nucleus 20 of the metal intermetallic compound エネルギ is more energetically stable than the free atom. Therefore, the crystal nucleus 20 of the intermetallic compound が continues to grow by the driving force of diffusion until it reaches the composition in the equilibrium state (hook, abundance ratio of Θ phase-h: a). In general, the product nuclei tend to be close to hemispherical and large in size on the substrate because they are intended to be stabilized by minimizing the surface area and minimizing the interfacial energy. The reason why the size of a single element increases is obvious from the fact that, for a similar shape, the surface area increases in proportion to the square of the radius, and the number of atoms increases in proportion to the cube of 3

In addition, when a target having a composition in which the concentration of B atoms 22 is X 1 is sputtered, in addition to the phase 0 of the metal intermetallic compound and the A atoms 2 in an equilibrium state after a lapse of time sufficient for diffusion. There is one crystalline phase α. Excess Αatom 21 diffuses freely without being constrained due to the substantial absence of the B element to be repelled (反 22, but most of it is the substrate 2 0 1 with a high diffusion coefficient). It will be uniformly distributed on the surface and form a Λ atom 21 rich layer 30 (Fig. 4).

The process described above is time dependent. For example, the higher the temperature of the substrate 101 is, the higher the diffusion rate is, and within a certain time, the height of the crystal nucleus 20 of the intermetallic compound can be increased. In addition, the frequency of occurrence of the crystal nucleus 20 of the metal intermetallic compound is affected by the material of the base formed on the surface of a certain plate 101. By appropriately selecting this, a desired projection density can be obtained. The material of the base is good in composition and temperature Any material may be used as long as it is stipulated in, but for magnetic disk media, alloys of glass, nickel (hereinafter abbreviated as Ni) and phosphorus (hereinafter abbreviated as P), Co alloys, carbon, etc. are preferably used. .

In addition, if the surface of the substrate 101 is processed to increase the surface area, the metabolic energy also increases, which has the effect of locally promoting the growth of crystal nuclei 20 of the metal intermetallic compound. Therefore, when processing marks are formed on the surface of the substrate 101, crystal nuclei 20 of the intermetallic compound can be arranged along the processing marks.

For example, in a magnetic disk drive, the projections of the crystal nuclei 20 of the metal intermetallic compound are formed in a predetermined direction on the opposing surfaces of the magnetic disk medium and the magnetic head, and the arrangement of both projections is By arranging the magnetic disk medium surface so as to intersect each other when viewed from the vertical direction, the contact area is reduced, and good sliding reliability can be realized.

The target for forming the projections by the crystal nucleus 20 of the intermetallic compound used in the present invention may be any system as long as it can generate an intermetallic compound as described above. A1 is selected as an atom because it diffuses easily even at low temperatures, improving the thermal stability of the intermetallic compound, and the reaction between the intermetallic compound and the films formed above and below the protrusions of this intermetallic compound In addition, the high melting point metal element (Co, Cr, Cu, I½) with a melting point of 100 ° C. or more as a B atom can be formed because the density can be reduced and fine intermetallic compound protrusions can be formed at a high density. , Mn, Mo, Ni. Pd , Pt, V, W , etc.) and _c also be desirable to select a configured intermetallic compound from a method for producing a target, the Λ1 as a atoms from ¾ locations prices, Select an element selected from Cr, Co, Mo, V, and W as the B atom. It is preferred. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a part of a state diagram illustrating the process of forming protrusions. Figures 2 to 4 The figure is a diagram for explaining the process of forming protrusions. FIG. 5 is a sectional view of a magnetic disk medium according to an embodiment of the present invention. FIG. 6 is a part of an A1-Cr phase diagram illustrating a process of forming protrusions. FIG. 7 is a diagram showing an AFM image of the surface of the magnetic disk medium that is Embodiment 1 of the present invention. FIG. 8 is a diagram showing an AFM image of the surface of a magnetic disk medium using an A1-0% Cr target. FIG. 9 is a diagram showing an AFM image of the surface of a magnetic disk medium using an A1-5% Cr target. FIG. 10 is a diagram showing an AFM image of the surface of a magnetic disk medium using an A1-12.5 Cr target. FIG. 11 is a sectional view of a magnetic disk medium according to a second embodiment of the present invention. FIG. 12 is a sectional view of a magnetic disk medium according to a third embodiment of the present invention. FIG. 13 is a schematic view of a magnetic disk drive according to the present invention. FIG. 14 is a schematic diagram of a magnetic head applied to a magnetic disk drive according to Embodiment 4 of the present invention. FIG. 15 is a schematic diagram of a magnetic disk medium applied to a magnetic disk device according to Embodiment 4 of the present invention. FIG. 16 is a diagram showing the results of analyzing the respective ratios of A 1 and Cr deposited on the substrate by sputtering an Al—Cr target. FIG. 17 is a diagram showing the relationship between the process density and the protrusion density and the process conditions. FIG. 18 is a diagram showing the effect of the protrusion on the magnetic characteristics and sliding reliability. FIG. 19 is a diagram comparing the magnetic properties of a configuration in which the protrusion is formed below the magnetic film. FIG. 20 is a diagram showing the sliding reliability of the magnetic disk device according to the fourth embodiment of the present invention. FIG. 21 is a diagram showing the reflectance when a projection is formed on a silicon wafer by the method of the present invention.

FIG. 22 is a view for explaining the projection height in the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Next, the present invention will be described with reference to the drawings.

FIG. 5 is a sectional view of a magnetic disk medium according to the first embodiment of the present invention. First, Λ1 alloy substrate with an outer diameter of 95 strokes, an inner diameter of 25 mm, a thickness of 0.8, a disc with a concentric hole at the center of the hidden surface, and a center line average roughness Ra of 0.3 nra to 5 nm. 1 Add N'i and P alloy. The A1 alloy substrate 101 on which the Ni and P alloys are plated is heated by a lamp in a vacuum for the purpose of degassing and improving magnetic recording characteristics. At this time, the applied power is controlled so that the alloy layer 103 formed later has a temperature such that the alloy layer 103 has predetermined magnetic characteristics. After heating, an alloy layer 102 of chromium (hereinafter, referred to as Cr) and titanium (hereinafter, referred to as Ti) is formed on the substrate 101, and furthermore, covanolate (hereinafter, referred to as Co), Cr, and platinum (hereinafter, referred to as Pt). ) Are sequentially formed. The alloy layer 103 has a function of magnetic recording. The Cr and Ti alloy layer 102 has a good adhesion between the Co-Cr Pt alloy layer 103 on the substrate 101 and the crystal grain size and crystal orientation of the Co-Cr- alloy layer 103. Has the effect of forming a good controllability. The material used for the alloy layer 102 and the alloy layer 103 may be any other material as long as it has the functions and effects described above. The material of the substrate 101 is also non-magnetic and may be any material as long as there is no problem in flatness and strength.

Thereafter, the substrate 101 is processed for a predetermined time by a processing device provided with a helm introducing mechanism, and the substrate is brought to a predetermined temperature suitable for forming A1 and the intermetallic compound projections 1 () 4. Cooling. This is unnecessary if the substrate temperature has dropped to a predetermined temperature due to radiation, conduction, or the like while the substrate 101 is being transported from the processing chamber to the processing chamber. Any gas may be used as long as it has a cooling effect. On the other hand, if the temperature of the substrate 101 is too low, the substrate 101 is heated again to a predetermined temperature. Subsequently, a projection〗 04 of an intermetallic compound of Λ1 and Cr is formed on the alloy layer 103 by sputtering a target made of Λ1 and Cr.

Further, a protective film layer 105 for protecting the alloy layer 103 and the protrusions 104 from mechanical or chemical contact is subsequently formed.

The device that formed the magnetic disk of this embodiment was an MDP250 machine manufactured by Ilinterbach, Inc. W

The in-line sputtering system has a substrate heating chamber, a substrate cooling chamber, and a substrate processing chamber capable of performing a plurality of magnetron buttering operations. However, any apparatus can be used as long as the substrate temperature control and sputtering can be performed. The 1 0 2, 1 0 3, 1 0 4, 1 0 5 during the processes for forming the respective layers of be held under pressure sense 2. 0 X 10- ⁵ Pa or less of such antioxidant desirable.

Hereinafter, a method for forming the protrusions 104 will be described in detail with reference to FIG. 2, FIG. 3, FIG. 4, and FIG. Figure 6 is a part of the Al-Cr equilibrium phase diagram with an intermetallic compound phase. FIG. 2, FIG. 3, and FIG. 4 are views for explaining the process of forming protrusions. In FIG. 6, the vertical axis indicates temperature, and the horizontal axis indicates the concentration of Cr atoms in the Λ1-Cr system. For example, at point Y in FIG. 6 where the concentration of Cr atoms is 10 atomic% and the temperature is 500 K, the solid solution phase α of A] and the intermetallic compound phase 金属 are present in a ratio of about 1: 4. Indicates that it is energetically stable. Therefore, if the concentration of Cr atoms is 10 atomic% and the temperature is 500 K, β will be enough to cause sufficient diffusion, and if the time is maintained, phase and phase 0 will be formed in a ratio of 1: 4. In the state where the concentration of Cr atoms is 12.5 atomic% and the temperature is 500 K, only phase can be obtained.

Next, a projection made of an intermetallic compound of A1 and Cr is formed on the alloy layer 103 by sputtering a target made of A1-10 at% Cr. The target is obtained by uniformly mixing and sintering fine powders of Λ] and Cr, and the intermetallic compound mainly composed of Al ₇ Cr and Al. Cr are uniformly mixed. . As can be seen from FIG. 6, the target has a Cr content of 10 atomic%, so that the atoms of A1 and Cr are sputtered and reach the alloy layer 103, and diffuse on the surface of the alloy layer 103. When the equilibrium state is reached, the ratio of the intermetallic compound Al ₇ Cr is 80%, and the rest is A1 (Al: Al ₇ Cr = l: 4). In an actual process, it varies depending on the process conditions such as the temperature of the substrate 101 and the formation time. The actual sputtered target To check if atoms have reached the substrate at a given ratio

Constant analysis was performed by the ICPS (Inductively-Coupled Plasma Spectroscopy) method. The results are shown in FIG. The analysis was performed at a Cr concentration of 5% and] 0%. It can be seen that atoms having substantially the same quantitative ratio as the target have reached the alloy layer 103. The target material is not limited to the above-mentioned 10 atomic% Cr and may be any type of material as long as it can form an intermetallic compound phase in an equilibrium state. The process by which the intermetallic compound protrusions are formed on the alloy layer 103 is the same as in FIGS. 2, 3, and 4.

First, as shown in Figs. 2 and 3, when the target is shattered, A1 and each element reach the alloy layer 103. In the alloy layer] 0 3 1-, each atom of Al and Cr is bonded to form a crystal nucleus 20 of a metal intermetallic compound Al ₇ Cr. The 供給 1 and Cr atoms supplied continuously continue to reach the same probability to the place where the crystal nucleus 20 of the gold intercalation compound on the mixed debris 103 is not located. ^ of ^ things because better formed is energetically more stable than is the atomic free wipe, sintered products nucleus 2 0 of intermetallic compound A1 ₇ 0 driving force acts diffusion up to the composition of the equilibrium Will continue to grow. The diffusion coefficient at the surface of the alloy layer 103 is so large that the metal alloy can be formed even at a low temperature of 600 K or less in the case of the first material. In addition, the alloy ^ 103 may contain atoms forming an intermetallic compound with each of Al and Cr, but the atoms of the alloy layer 103 may be included before the target is shattered. Has already formed a stable crystal structure, does not actually react at low temperatures below 600Κ, and the reaction on the surface of the alloy layer 103 is actually limited to バッ] and Cr atoms. Is done. In general, the product nucleus 20 of the residual compound is intended to be stabilized by minimizing the surface area and minimizing the interfacial energy. is there. The reason that one dimension becomes larger is that, if the shape is similar, the surface area is proportional to the square of the radius, and the fundamental number is proportional to the cube of 3. It is clear from the increase.

In addition, the above Λ1-10 atoms. /. At the Cr concentration, even in the equilibrium state, there is an excess of A1 atoms in addition to the intermetallic compound phase. These A1 atoms diffuse freely without being constrained because there is substantially no Cr to be reacted, but as shown in Fig. 4, most of them are located on the outermost surface of the alloy layer 103 with a high diffusion coefficient. It will be uniformly distributed as A1 rich layer. This excess Λ1 atom is stabilized once it forms a crystal lattice. If the excess A1 atoms are so small that they cannot form a crystal lattice, they are insignificant, if any, even if they diffuse, and in any case, are substantially equivalent to the adjacent alloy fe; 103 or the overcoat layer 105. Will not react. However, atoms of alkali metal, alkaline earth metal, and halogen element have high reactivity and cannot be used as a projection material, and are not used in the present invention.

The process described above is time dependent. Since the diffusion process takes a certain amount of time, it is limited within a limited time, and generally does not reach an equilibrium composition.

FIG. 7 shows the result of observing the surface shape of the magnetic disk medium of the present embodiment formed as described above using an atomic force microscope (AFM). Here, as shown in Fig. 22, the projection height is defined as the mode value in the histogram of the height measured by the AFM as the projection height 0, and the distance from the surface at the projection height 0 as the projection height. In the area of Fig. 7, the density of the projections was 2.5 x 10 / s and the height of the projections was 30 _nm on average.The density of the projections and the height of the projections were as shown in Fig. 17. From the viewpoint of magnetic properties and sliding reliability, it is desirable that the density of the projections is 1.0 X 10 '嗰 / or more, and the average thickness of the projections is 10 nm or more. At the target input power and sputtering time, the higher the substrate temperature, the easier the diffusion of atoms. As a result, the height of the protrusion increases, and the target is injected to increase the protrusion density. It is necessary to increase the power or the sputtering time, but if it is excessive, the diameter of the projections themselves increases, the projections coalesce to form huge projections, the number of projections decreases, and finally the flatness is almost flat Surface.

In addition, as shown in FIG. 4, the protrusions and flat portions were analyzed by Auger electron spectroscopy (AES) in the depth direction of the magnetic disk medium of Example 1 without the protective film layer 105 being formed. It was confirmed that Λ1 was distributed on the outermost surface except for the protruding portions, and the structure was such that the intermetallic compounds of A1 and Cr existed on the protruding portions. The AES analysis of the magnetic disk medium of Example 1 with the protective film layer 105 formed up to the protective film layer 105 showed that the 1-atom alloy layer 103 and the protective film were analyzed. It was confirmed that the diffusion into layer 105 was substantially negligible. In addition, a protrusion of an intermetallic compound was formed by an Al-Cr target having a Cr concentration of 10%, and the protective film layer 105 was formed. The magnetic disk medium of Example 1 (projection density: 2.5 × 10 ^The magnetic properties of ¹² protrusions / m ² and an average protrusion height of 30ηπι) were examined. In addition, the sliding reliability of a magnetic disk medium having a 3 nm lubricating film composed mainly of perfluoropolyether was examined. The coercive force He and the squareness ratio S * were used as parameters for the magnetic properties, and the initial adhesive force, initial tangential force, and the adhesive force after 10,000 times of CSS were used as the sliding reliability parameters. VS (Vibrating Sample Magnetometer) was used for measurement of He and S *. The sliding test used a magnetic head known to those skilled in the art. As a comparative example, a magnetic disk medium prepared under the same conditions without forming the protrusions 104 was prepared, and the protrusions of the intermetallic compound were formed using the Λ] -Cr target having a Cr concentration of 10%. The results for the formed magnetic disk media of Example 1 and Comparative Example are shown in FIG. As a result, it can be seen that the magnetic disk medium having the protrusion of Mi Example 1 has the same magnetic properties as the comparative example, and the dynamic reliability is better than the comparative example.

Next, a magnetic recording apparatus using the magnetic disk medium of the first embodiment was changed to a 13M magnetic recording apparatus. Show. The magnetic head 3 is provided in the magnetic disk device 5 so as to face the magnetic disk medium 1. The spindle motor 2 rotates the magnetic disk medium 1, and the magnetic head 3 is positioned at a predetermined position on the magnetic disk medium 1 by the head drive unit 4. The recording / reproduction is performed by the magnetic head 3 floating above the magnetic disk medium 1 when the magnetic disk medium 1 rotates.

Assuming that the flying height of the magnetic head is 0.02 zm, the coercive force H _C (L) measured in the running direction (circumferential direction of the magnetic disk medium) of the magnetic disk medium of the embodiment] the ratio between the traveling direction and the vertical direction of the magnetic heads in the plane of the disk media coercivity Hc measured in (magnetic radial direction of the disk medium) (R), measured to _{H c (L) / Hc (} R) ] 1 and higher, high output was obtained at high linear recording density, and the S / N value was as good as 6.

Fine polishing marks called texturing are formed on the surface of the A1 alloy substrate 101 substantially in the running direction of the magnetic head, and the alloy layers 102 and 103 are formed on the substrate 101. Then, Hc (L) / Hc (R) can be increased. Usually magnetic recording it is necessary to increase the order circumferential coercive force Hc in the running direction, i.e. the magnetic disk medium head the magnetic (L) is required _{H c (L) Hc (R} ). Since the projections 1 0 4 of the present embodiment may be formed on the alloy layer 1 0 3, without the value of Ri by the fact that the formation of the projections 1 0 4 Hc (L) / H c (R) is reduced, A magnetic disk medium having Hc (L) / Hc (R) of 1.1 or more can be realized. In particular, in order to improve the output at a high linear recording density of 100 kBPI or more, the value of Hc (L) / Hc (R) is preferably set to 1.1 or more and 1.5 or less. Hc (L) / H value of _c (R) 1. 5 exceeds the undesirable reduction in output at high linear recording density when ® corner of head to magnetic has增becomes remarkable. Further, in Example 1, the surface shapes of the magnetic disk media manufactured by changing the Cr concentration of the Ato Cr target were compared. There are four types of samples with different concentrations of Cr in the target Cr target, 0, 5, 12.5, and 20 percent, respectively. In the same manner as in the above test, the surface was observed by AFM without forming the protective film layer 105, and the composition of the protruding portion and the flat portion was analyzed by Auger electron spectroscopy (AES).

First, when a target with a Cr concentration of 0%, that is, a pure A1 target is used, no intermetallic compound that should form a projection can be generated, and therefore, as shown in the AFM image in Fig. 8, only a substantially flat surface is obtained. I can't get it. When AiiS analysis was performed on the surface, A1 was detected on the entire surface. Note that the oblique line in FIG. 8 is due to a scratch generated during the removal of the magnetic disk medium.

Next, Fig. 9 shows an AFM image of the surface when using a target with a concentration of 5 atomic%. There is more excess of the intermetallic compound than the intermetallic compound that forms the protrusions.Λ1 The thickness of the A1 rich layer in FIG. 4 is large.ΛThe valleys are filled in and the protrusions of the intermetallic compound become unclear. I have. As a result of composition analysis of the surface by AES, A1 was detected on the entire surface. For this reason, the 3.5 nm Λ1 rich layer was scraped off with a submerged etch, and surface analysis was performed again by AES.As a result, the composition ratio of the protruding portion was approximately 11% Cr, and the intermetallic compound was the main component. It was confirmed that. From this, even when a target with a Cr concentration of 5 atomic% is used, the contribution of the metal intermetallic compound to the formation of protrusions is recognized. As in the case of the above concentration of 10% (child./.), The results of the sliding reliability test are also shown in Fig. 18. As a result, when the Cr concentration is 5 atomic%, It can be seen that although the Cr concentration is not more than 10 atoms //, it is more effective in the magnetic properties and sliding reliability than when no projection is formed.

In addition, the Cr concentration is 12.5 atoms. Figure 10 shows an AFM image of the surface when the target is riverbed. Λΐίίί (了-((τ) atoms are also substantially consumed to form intermetallic compounds, and no surplus is left in the flat part. This is confirmed by the AES analysis. When a target with a Cr concentration of 20 atomic% was crucible, From the AFM image and AES analysis of the surface, it was confirmed that virtually all of the Λ1 and Cr atoms were consumed to form the metal intermetallic compound, and no surplus atoms remained in the flat part.

However, if the substrate temperature is low or the holding time is short even if the substrate temperature is high, the state where Al and Cr atoms are sputtered on the flat part is fixed as a non-equilibrium state.

The intended purpose can be achieved by using a target in which the concentration of the added atom (Cr in this embodiment) is 0.4 to 1 times the concentration of the atoms constituting the intermetallic compound. . In the case of the A1-Cr system of the present embodiment, the metal intermetallic compound Al ₄ Cr can also form protrusions, so that the Cr concentration is preferably 5 atomic% or more and 20 atomic% or less. Similarly, in the A1-Co, A1-Mo, Al-W, and Al-V systems, Co is 7-29 atomic%, Mo and V force are S3-25 atomic%, and W is 3-20%. It is suitable.

Next, a second embodiment will be described. FIG. 11 is a sectional view of a magnetic disk medium according to a second embodiment of the present invention. Λ1 Alloy Ni and P alloy on 1 alloy substrate 101. A Cr-Ti alloy layer 102 is formed on the A1 alloy substrate 101 on which the Ni and P alloys are plated, and a Co-Cr-Pt alloy layer 103 is sequentially formed. After forming an amorphous carbon film on the alloy layer 103 with a thickness of 3 nm by sputtering, a metal atom compound is protruded in the same manner as in Example 1 above, using a target of 10 atomic% and 0 target. Was formed. As a result of AFM observation of the surface of the magnetic disk medium, the carbon film カーボン 06 provided between the alloy phase 103 and the projection 104 of the intermetallic compound has an effect of increasing the density of the projection 104. It turned out to play. In addition, by shortening the distance between the target and the substrate, the probability that the target material adheres to the substrate can be increased, and the density of the intermetallic compound protrusions 104 can be increased. FIG. 12 is a sectional view of a magnetic disk medium according to a third embodiment of the present invention. A projection 104 of an intermetallic compound was formed on a glass substrate 101 under the same conditions as in Example 1. Then, an alloy film 102, 103 and a protective film 105 were formed thereon. Observation of the surface of the magnetic disk medium of Example 3 by observation revealed that the protrusions 104 of the intermetallic compound were formed in the same manner as in Example 1.

Next, Example 1, Example 3, alloy films 102, 103, and protective film 105 were formed under the same conditions, and the magnetic characteristics were compared without forming protrusions. Therefore, the values of He and were measured. The results are shown in FIG. In Example 3 in which the protrusion 104 was below the alloy dust〗 03, no protrusion was formed, and it can be seen that the magnetic properties were lower than in the example. This is because the alloy layer 03 contributing to magnetic recording is waving. On the other hand, the value of Hc (L) / Hc (R) could be set to 0.95 or more and 1.05 or less, and a decrease in output at high linear recording density could be prevented.

For the purpose of reducing the capacity and height of the magnetic disk device, it is preferable to use a ceramic substrate such as glass for the magnetic disk substrate because the magnetic disk medium can be made thinner than the metal substrate. In the case of glass substrates, since it is impossible to form a texturing to the surface as used in the A1 alloy board, magnetic value of _{Hc (L) / H c (} R) is greater than 1.0 5 A disk medium cannot be formed. In the case of a glass substrate, instead of forming texturing on the substrate surface, the magnetic disk of Example 3 in which the intermetallic compound protrusion 104 was formed in contact with the alloy film 103 on the side of the alloy film 103, that is, on the substrate 10.1. It is preferred that the medium is flowing. According to the third embodiment, the direction of magnetic anisotropy can be made uniform even in a magnetic disk medium having a glass substrate, so that the value of H _C (L) / H (:( R) is 0.95. If Hc (L) / Hc (R) is less than 0.95, the coercive force in the row direction of the head decreases, and at a high linear recording density of lOOkBPI or more, Here, the projections 104 are not preferable because the projections 104 can be formed on the glass substrate 101 in a single contact as in the third embodiment, but particularly the fine projections 104 are formed. In this case, non-magnetic Co-Cr alloy, non-magnetic Co-Cr-Ta alloy or 1¾ / 13, 21 <, 11812 1? An underlayer consisting of an alloy with a main component of not less than 5 nm and not more than 100 nm is formed. Fine protrusions 1◦4 can be formed at high density.

Next, a fourth embodiment in which the present invention is applied to a magnetic disk apparatus will be described.

FIG. 14 is a schematic diagram of the magnetic head 3 according to the fourth embodiment. The magnetic head 3 according to the present embodiment includes a slider 31 and an element 32 for performing recording / reproduction on the magnetic disk medium 1. After striations were formed on the surface 31 1 of the slider 31 facing the magnetic disk medium 1 by a mechanical method, the element 32 was formed on the slider 31. Next, a magnetic head 3 having an intermetallic compound protrusion 30 was formed on the opposing surface 311 of the slider in the same manner as in Example 1. Further, a carbon target was sputtered in an argon-20% hydrogen atmosphere to form a protective film on the surface of the magnetic head 3 facing the slider 31 and the element 32, thereby obtaining the magnetic head 3. However, the target used when the protrusion was formed is 1-7 atomic%. The material and process of the protective film are not limited to those described above. The target used for forming the projections may be of any type as long as it can generate a phase of a metal intermetallic compound in an equilibrium state in an amount of 40% or less.

FIG. 15 shows a schematic diagram of the magnetic disk medium in the fourth embodiment.

First, a polishing table was rotated while rotating a disk-shaped A1 alloy substrate with an outer diameter of 95 mm, an inner diameter of 25 mtn, a thickness of 0.8 mm, and a concentric hole in the center. Is pressed to mechanically work to give a streak in the circumferential direction. The surface roughness is controlled so that on average Rp is in the range of 4 to 8 nm.

The magnetic disk medium 1 having the intermetallic compound projections 0 was formed on the substrate processed as described above in the same manner as in Example 1. The target used when the protrusion 10 was formed was A1-7 atomic%. The target can be any system capable of producing an intermetallic compound phase in equilibrium at 40% or more. It may be.

The method of forming a streak on the opposing surface is not limited to the mechanical method described above, but may be a method such as a combination of photolithography and dry etching, as long as the surface area is locally increased approximately at a constant cycle. .

A magnetic disk drive using the above magnetic disk medium 1 and magnetic head 3

When configuring 5, the arrangement of the protrusions of both the magnetic disk medium 1 and the magnetic head 3 is arranged so as to intersect with the surface of the magnetic disk medium from the lead | direction. As a result, the contact area between the opposing surfaces of the magnetic disk medium 1 and the magnetic head 3 is reduced, and the sliding characteristics are improved.

With respect to the magnetic disk device of Example 4, the initial tangential force, the initial viscous force, and the adhesive force after 10,000 times of CSS were measured as parameters of the sliding characteristics. Similarly, the measurement was performed using a magnetic disk device composed of a combination of a magnetic head without protrusions and a magnetic disk medium as a comparative example. The results are shown in FIG. It can be seen that the magnetic disk device of Example 4 is less likely to stick between the magnetic head and the magnetic disk medium than the comparative example.

In Protrusion 5, a mirror-polished silicon wafer was formed with protrusions of an intermetallic compound.

On a silicon wafer substrate on which an oxide film of 100 ± 10 nm is formed by heating, protrusions of intermetallic compounds of 1 and Co are formed by sputtering a target consisting of A1-14 atomic% Co. The target is not limited to the target made of A1% Co and may be any type of target as long as it can generate an intermetallic compound phase in an amount of 40% or more in an equilibrium state. The reflectance of the mirror obtained by the shearing was measured using a mercury lamp and a reflectance measuring device using a river. Figure 21 shows the results. The reflectance can be controlled by changing the formation temperature and the formation time. Industrial applicability

According to the present invention, it is possible to provide a magnetic disk device which is less likely to cause adhesion between the magnetic head and the magnetic disk medium and has excellent sliding resistance.

In addition, it is possible to shorten the time of one processing, to easily maintain the shape after forming the protrusions, and to easily manufacture magnetic disk media and magnetic heads that simultaneously satisfy the magnetic recording characteristics and the sliding reliability. Can be configured.

Claims

The scope of the claims

1. An alloy layer containing cobalt (Co) as a main component is formed on a substrate by sputtering, and aluminum (A1) atoms and chromium, cobalt, molybdenum, vanadium, tungsten, copper, iron, manganese, and the like are formed on the alloy layer. Nickel, noradium or platinum (0,0), 1 ^ 0 ^, 01 6 ^, 1 ^ or? Forming an island-like protrusion by buckling a target composed of atoms of one kind of element selected from the above, and forming a protective film layer on the alloy layer and the protrusion. A method for manufacturing a magnetic disk medium.

2. An alloy layer containing cobalt (Co) as a main component is formed on the substrate, a carbon layer is formed on the alloy layer, and aluminum (Λ1) atoms and chromium are formed on the carbon layer. Konoroku, molybdenum, vanadium, tungsten, copper, iron, manganese, nickel, palladium or platinum (0, (; 0,1 ^ 0,, [: 11,, 1 ^ ,. \ 'do (1 or Forms an island-like projection by sputtering a target composed of atoms of one kind of element selected from Pt), and forms a carbon layer and a protective film layer on the projection. A method for manufacturing a magnetic disk medium.

3. Aluminum (A1) atoms and chromium, cobalt, molybdenum, vanadium, tungsten, copper, iron, manganese, nickel, palladium or platinum (0 0,! ^ 0, (1_1, 6,1 ^, ,? (1 or ^ or 1 ^) are formed by sputtering a target composed of atoms of a certain kind of element to form a ¾-shaped protrusion, and the substrate and the protrusion are formed. A method for manufacturing a magnetic disk medium, comprising: forming an alloy layer containing cobalt (Co) as a π component thereon; and forming a protective film on the alloy dust.

4. The composition of the target element is Λ 1 -X atomic% (χ = 5-20), Λ 1 -X atomic percent (x = 3-25), Al-xlJj (7-% Co (x = 7 -29), A xfti% V (x = 3 25) or Λ1 xJi 4. The method for manufacturing a magnetic disk medium according to claim 1, wherein the ratio is% W (x = 3-20).

5. A substrate, an alloy layer containing cobalt (Co) as a main component formed on the substrate, an island-shaped protrusion made of an intermetallic compound formed on the alloy layer, and an upper surface of the alloy layer and the protrusion. A magnetic disk medium comprising a formed protective film layer.

6. A substrate, an alloy wind mainly composed of cobalt (Co) formed on the substrate; a carbon layer formed on the alloy layer; and a gold-based compound formed on the carbon layer. A magnetic disk medium comprising an island-like protrusion, a carbon layer and a protective film layer formed on the protrusion.

7. The substrate, the island-shaped protrusions made of a metal compound formed on the substrate, the cobalt (Co) -based alloy layer formed on the substrate and the protrusions, and the alloy! A magnetic disk medium comprising a formed protective film layer.

8. The above-mentioned protrusions are composed of aluminum (Λ1) atoms and chromium, covanolate, molybdenum, vanadium, tungsten, copper, iron, manganese, nickel, nickel radium or gold (0, (： 0 ^ 0, ¥ ^, ( 8. An intermetallic compound composed of atoms of a kind of element selected from 1], 0 ^ 11,] \, and de (1 or? 1;). A magnetic disk medium as described.

9. Chromium, cobalt, molybdenum, vanadium, tungsten, copper, iron, manganese, nickel, palladium or platinum (Cr, Co, Mo, V, W, Cu, Fe, Mn, Ni, Pd) in the intermetallic compound 9. The magnetic disk medium according to claim 8, wherein the concentration of atoms of a kind of element selected from among Pt) is 1 atomic% or more and 30 atomic% or less.

10. The island-shaped protrusion is made of an intermetallic compound composed of aluminum (A1) atoms and a high melting point metal element having a melting point of 100. Magnetic disk media.

11. The magnetic disk medium according to claim 5, wherein the island-like projections contain a metal intermetallic compound at a ratio of 40% or more in an equilibrium state.

1. The magnetic disk medium according to claim 5, wherein the density of the island-shaped projections is 1.0 × 10 ¹² or more on average, and the height of the projections is an average of lOnm or more. .

1 3. The ratio of the coercive force Hc (L) measured in the circumferential direction of the magnetic disk medium to the coercive force He (R) measured in the radial direction of the magnetic disk medium, Hc (l,) / Hc 7. The magnetic disk medium according to claim 5, wherein (R) is 1.i or more and 1.5 or more.

1.The ratio of the coercive force He (L) measured in the circumferential direction of the magnetic disk medium to the coercive force Hc (R) measured in the radial direction of the magnetic disk medium, llc (L) / Hc ( 8. The magnetic disk medium according to claim 7, wherein R) is 0.95 or more and 1.05 or less.

1 5. In the magnetic head consisting of the element for recording / reproducing to / from the magnetic disk medium and the slider mounting the end,

A magnetic head characterized in that the slider has an island-shaped protrusion made of a metal intermetallic compound on one side (a surface) with respect to a magnetic disk medium.

1 6. The island-shaped protrusions are made of aluminum (ΑΠ-no-hara and chromium, covanolate, molybdenum, vanadium, tungsten, copper, iron, manganese, nickel, vanadium or platinum (0, (: 0 ^ 0, ¥, \ ^ 6. The magnetic material according to claim 5, wherein the magnetic material is made of a gold compound composed of atoms of a kind of element selected from (^, 6, 1 ^, ^, (1 or 00). Head.

17. The island-shaped protrusion is made of a gold alloy or a compound composed of aluminum (Λ1) atoms and a refractory metal element having a melting point of 100 ° C. or higher. Magnetic head as described.

18. A magnetic disk medium, a magnetic head provided to face the magnetic disk medium and performing recording and reproduction by floating on the magnetic disk medium, and a magnetic head mounted on the magnetic disk medium A magnetic δ disk device, comprising: a head driving unit positioned at a predetermined position; and a spindle motor for rotating the magnetic disk medium.

The magnetic disk medium includes a substrate, an alloy layer mainly composed of cobalt (Co) formed on the substrate, island-shaped protrusions made of an intermetallic compound formed on the alloy layer, and the alloy layer; A magnetic disk device having a protective film layer formed on a projection.

0 1 9. A magnetic disk medium, a magnetic head which is provided to face the magnetic disk medium and performs recording and Z reproduction by floating above the magnetic disk medium, and the magnetic head A magnetic disk drive f® including a head drive unit positioned at a predetermined position on a medium, and a spindle motor for rotating the magnetic disk medium;

5 The magnetic disk medium includes a substrate, an alloy layer mainly composed of cobalt (Co) formed on the substrate, a carbon layer formed on the alloy layer, and a metal layer formed on the carbon layer. A magnetic disk device comprising: an island-shaped protrusion made of a compound; a carbon layer; and a protective film layer formed on the protrusion.

20. A magnetic disk medium, a magnetic head provided opposite to the magnetic disk medium for performing recording and reproduction by floating above the magnetic disk medium, and a magnetic head mounted on the magnetic disk medium In a magnetic disk drive comprising a head drive unit positioned at a predetermined position, and a spindle motor for rotating the magnetic disk medium,

The magnetic disk medium is mainly composed of a substrate, a five-island protrusion formed of an intermetallic compound formed on the substrate, and cobalt (Co) formed on the substrate and the protrusion. A magnetic disk drive comprising: an alloy layer; and a protective film layer formed on the alloy scrap.

21. The magnetic head comprises an element for performing recording / reproducing on the magnetic disk medium and a slider on which the element is mounted,

21. The slider according to claim 18, wherein the slider has an island-shaped protrusion made of an intermetallic compound on a surface facing the magnetic disk medium, and the slider and a protective film layer formed on the protrusion. Magnetic disk unit.

22. The magnetic disk medium has a streak formed in a specific direction on the surface of the substrate, and the island-shaped protrusions formed on the magnetic disk medium are formed on the surface of the substrate. The magnetic head is formed preferentially in a direction along the streak, and the magnetic head has a streak formed in a specific direction on a surface of the front slider facing the magnetic disk medium, and the magnetic head is The island-shaped projections formed on the magnetic disk medium are preferentially formed in the direction along the streaks of the slider, and the arrangement of the island-shaped projections of the magnetic disk medium and the S-shaped projections of the magnetic head are: 22. The magnetic disk drive according to claim 21, wherein the magnetic disk drives are arranged so as to cross each other.

23. The island-shaped protrusions are made of aluminum (Λ1) and chromium, cono-cort, molybdenum, vanadium, tungsten, copper, iron, manganese, nickel, palladium or platinum (Cr, Co, Mo, V, 33. An intermetallic compound composed of an element f of one kind of element selected from W, Cu, i''c, Mn, Ni, Pd or I). The magnetic disk drive according to the above.

2 4. The front island-like protrusions are aluminum (Λ 1) particles and have a melting point of 1000. The magnetic disk device according to claim 18, wherein the magnetic disk device is made of a metal compound composed of a high melting point metal having a melting point of C or higher.