JPH03189930A - Manufacture of perpendicular magnetic recording disk - Google Patents

Abstract

PURPOSE:To prevent the sticking of a head on the medium by forming a plating primary layer on a disk substrate, processing the surface of the base layer into a rough surface having fine ruggedness, then forming a soft magnetic layer having high magnetic permeability, thereby allowing the surface to be a soft rough surface with fine ruggedness without decreasing the strength of the disk substrate. CONSTITUTION:The plating primary layer 22 is formed on a disk substrate 21, and the surface of the layer is worked to have a rough surface 23 having fine ruggedness of about 300 Angstrom . Then a soft magnetic layer 24 having high magnetic permeability is formed by electroplating on the rough surface 23 of the primary layer 22, on which a perpendicular recording layer 25 and protective layer 26 are successively formed. Since the total film thickness of the laminated layers is large sharp projections in the plating primary layer 22 are rounded on the surface of the protective lubricating layer 26 to be a soft rough surface 27 with fine ruggedness in the whole surface. Thereby, fear of the chipping at the projecting leading edge of the rugged rough surface caused by the contact or sliding of a magnetic head slider, is eliminated and the attraction of a head can be prevented, as well.

Description

[Detailed Description of the Invention] [Summary] A method of manufacturing a perpendicular magnetic disk suitable for use in a perpendicular magnetic recording type magnetic disk device, in particular, a glass that prevents a magnetic head slider from adhering without reducing the strength of the substrate. , or a method for manufacturing a perpendicular magnetic disk with a two-layer structure using a hard disk substrate such as ceramic, in which the soft magnetic layer and the perpendicular recording layer are The purpose of this technology is to easily make the surface of a laminated magnetic disk into a smooth surface with minute irregularities to prevent head adsorption. In manufacturing a perpendicular magnetic disk with laminated recording layers, a plating underlayer is formed on the disk substrate, and the surface is processed to have a rough surface with minute irregularities. The structure includes a step of forming a soft magnetic layer by a plating method.

[Industrial application field]

The present invention relates to a method for manufacturing a perpendicular magnetic disk suitable for use in a perpendicular magnetic recording type magnetic disk device, and in particular, a hard disk substrate made of glass or ceramic that prevents a magnetic heel slider from adhering without reducing the substrate strength. The present invention relates to a method of manufacturing a perpendicular magnetic disk having a double-layer structure using the present invention.

In magnetic disk drives, with the increase in capacity and recording density, the flying height of the magnetic nodal slider during recording and reproduction on the magnetic disk is becoming smaller and the probability of contact is increasing. For this reason, the surface of the magnetic disk is smoothed and a lubricant film is applied to prevent wear and damage to the magnetic disk surface and the magnetic nodal slider.

However, if the surface of the magnetic disk is too smooth, for example, CS S (Contact 5tart 5top
) During operation, the magnetic hent slider tends to be attracted and head crashes occur. Therefore, there is a need for a method of manufacturing a smooth perpendicular magnetic disk having a surface roughness that does not cause such magnetic hent slider attraction.

[Conventional technology]

Conventionally, the manufacturing method of perpendicular magnetic disks to prevent magnetic attraction of the slider has been to mechanically roughen the surface of a hard disk substrate made of glass or ceramic using wrapping tape, or so-called texturing. After forming a rough surface with minute irregularities by a method, a high permeability soft magnetic layer (also referred to as a soft magnetic backing layer) made of NiFe is formed on the rough surface of the disk substrate by sputtering or plating, On this soft magnetic layer, a perpendicular recording layer made of Co-Cr and a lubricating protective layer made of carbon, etc. to reduce friction and wear during contact sliding of the magnetic henode slider are laminated in order by the spankling method. Common.

The surfaces of the layers formed in this way on the rough surface of the disk substrate inherit the state of the phase surface in order, so that the surface of the uppermost lubricating protective layer, that is, the surface of the magnetic disk, is microscopic. The surface becomes rough with roughness, and this surface condition reduces the contact area with the magnetic slider and prevents the head from adsorbing.

However, as mentioned above, it is difficult to roughen the surface of the hard disk substrate 11 made of glass or ceramic to a predetermined surface roughness by directly texturing the surface.
In addition, the formed rough surface promotes the occurrence of cracks, lowering the strength of the substrate and making it more likely to break.

Therefore, in order to eliminate such drawbacks, Fig. 2 (a)
As shown in the figure, a plating base film 12 made of Ni-Fe with a thickness of 1,500 mm is deposited on a hard disk substrate 11 made of glass or ceramic by sputtering or the like, and plating is performed on the plating base film 12. Several μm by method
After forming a high permeability soft magnetic layer made of Nt-Fe with a film thickness of 3, the surface of the soft magnetic layer 13 is textured to form a rough surface having minute irregularities with a surface roughness of, for example, about 300. Make it 14.

Next, as shown in FIG. By sequentially forming the lubricating protective layer 6 by sputtering, the surface of the uppermost lubricating protective layer 16, that is, the surface of the formed magnetic disk, is the same as that of the perpendicular recording layer 15. The rough surface, which is successively inherited to the lubricating protective layer I6, reduces the area of contact with the magnetic slider without weakening the strength of the substrate, and prevents the magnetic slider from being attracted.

[Problem to be solved by the invention]

However, when the surface of the soft magnetic layer 13 is roughened by a texturing method, the fine unevenness of the rough surface 1
The surface of the magnetic disk in which the tip of the convex portion at 4 has a sharp shape, and the perpendicular recording layer 15 and the lubricating protective layer 16 are laminated in this order on the rough surface 14'' of the soft magnetic layer 13 also has the following characteristics:
Due to the thin film thickness of the perpendicular recording layer 15 and the lubricating protective layer 16, the shape of the uneven rough surface 14 of the soft magnetic layer I3 is clearly inherited and the tip of the convex portion has a sharp shape. , the magnetic hent slider comes into contact with the surface of the magnetic disk.
When sliding, the tip of the convex portion is easily chipped, and the chipped piece is interposed between the disk surface and the magnetic slider, damaging the disk surface and, in the worst case, causing a problem. there were.

In view of the above-mentioned conventional problems, the present invention has been developed to easily improve the surface of a magnetic disk on which a soft magnetic layer and a perpendicular recording layer are laminated, without weakening the strength of a hard disk substrate made of glass or ceramic. The object of the present invention is to provide a novel method for manufacturing a perpendicular magnetic disk that has a smooth rough surface with minute irregularities to prevent head adsorption.

Means for Solving Problem C8] In order to achieve the above-mentioned object, the present invention is directed to manufacturing a perpendicular magnetic disk in which a soft magnetic layer with high magnetic permeability and a perpendicular recording layer are laminated on a non-magnetic and hard disk substrate. , a step of forming a plating underlayer on the disk substrate and processing the surface into a rough surface with minute irregularities, and then forming the high magnetic permeability soft magnetic layer on the plating underlayer by a plating method. Contain and compose.

[For production]

In the manufacturing method of the present invention, the surface of a plating base layer formed on a non-magnetic disk substrate such as glass or ceramic to a thickness thicker than conventional methods is processed into a rough surface with minute irregularities by a texturing method. This facilitates the formation of the rough surface and does not reduce the strength of the disk substrate.

In addition, even if the tips of the convex parts on the finely uneven rough surface of the plating base layer are sharp, a soft magnetic layer with high magnetic permeability, a perpendicular recording layer, and a lubricating protective layer can be laminated in order on the rough surface. As the total thickness of each layer is thick, the condition of the finely uneven rough surface of the plating base layer is reduced to 11 m.
The surface of the subsequent lubricant protection layer, that is, the surface of the magnetic disk, is formed into a smooth surface with minute irregularities. As a result, the magnetic nodal slider comes into contact with the surface of the magnetic disk.
Even when sliding, the conventional phenomenon in which the tip of a convex part on a rough surface with minute irregularities is chipped is eliminated, magnetic attraction of the slider to the nodal slider is prevented, and the lubricating sliding characteristics are improved.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIGS. 1A to 1D are cross-sectional views of essential parts showing an embodiment of a method for manufacturing a perpendicular magnetic disk according to the present invention in the order of steps.

In this embodiment, as shown in FIG.
0.5 to 0.7 on the surface of I by sputtering method etc.
Plating base layer 22 made of Nt-Fe with a film thickness of about μm
The surface of the plating base layer 22 is processed by a texturing method into a rough surface 23 having, for example, minute irregularities of approximately 300 people's surface roughness, as shown in FIG. 1(b). This eliminates the possibility that the strength of the disk substrate 21 will decrease or that cracks will occur as in the conventional case.

Next, as shown in FIG. 1 (C1), a high magnetic permeability soft magnetic layer 24 made of Ni-Pe with a film thickness of 2 to 3 μm, for example, is formed on the rough surface 23 of the plating base layer 22 by electrolytic plating. Then, as shown in FIG. 1 (di), a vertical substrate layer 25 made of Go-Cr with a thickness of 0.2 μm and a lubricating protective layer 26 made of carbon with a thickness of 300 μm are further formed by sputtering as shown in FIG. By sequentially depositing the layers, the total thickness of each layer stacked on the plating base layer 22 is thick, so that the condition of the finely uneven rough surface 23 of the plating base layer 22 is the best that is inherited through each layer. The surface of the upper lubricating protective layer 26 is in a state where the parts that inherited the sharp protrusions from the finely uneven rough surface 23 of the plating base Jit 22 are blunted, and the entire surface becomes a smooth finely uneven rough surface 27. The formed magnetic disk can be easily obtained.

Therefore, there is no fear that the tips of the protrusions on the uneven surface 27 will be chipped due to contact and sliding of the magnetic hendo slider, and furthermore, head adsorption is prevented, and the lubricating sliding characteristics are improved.

〔Effect of the invention〕

As is clear from the above description, according to the method for manufacturing a perpendicular magnetic disk according to the present invention, the disk surface can be made into a smooth microscopic structure without reducing the strength of the non-magnetic disk substrate made of glass or ceramic. It has the advantage that it can be easily formed on a rough, uneven surface, prevents head adsorption, and provides a highly reliable perpendicular magnetic disk with excellent lubrication and sliding properties.

[Brief explanation of drawings]

Figures 1 (al~(dl) are cross-sectional views of essential parts showing one embodiment of the method for manufacturing a perpendicular magnetic disk according to the present invention in the order of steps; Figures 2 (bl~) illustrate a conventional method for manufacturing a perpendicular magnetic disk. Fig. 1 is a sectional view of the main parts for the purpose of the present invention. 26 indicates a perpendicular recording layer, 26 indicates a lubricating protective layer, and 27 indicates a smooth rough surface with minute irregularities. Tamaki J hippopotamus figure 2nd

Claims (1)

[Claims] In manufacturing a perpendicular magnetic disk in which a soft magnetic layer (24) with high magnetic permeability and a perpendicular recording layer (25) are laminated on a non-magnetic and hard disk substrate (21), the disk substrate ( 21) After forming a plating base layer (22) on the plating base layer (22) and processing its surface into a rough surface (23) with minute irregularities, the high permeability soft magnetic layer (21) is formed on the plating base layer (22). 24) A method for manufacturing a perpendicular magnetic disk, comprising the step of forming by a plating method.