JPS5832240A - Production of reproducing stylus detecting change of electrostatic capacitance value - Google Patents

Abstract

PURPOSE:To produce easily a reproducing stylus having a long lifetime, by implanting an ion through different directions directing toward areas including an intended part where an electrode part of the main body material of the reproducing stylus is formed and forming an electrode part into a diamond. CONSTITUTION:An intended area to form rubbing face and an electrode part are secured at the part of a raw material diamond. The material S of the main body of a reproducing stylus is worked previously so that its external form is equal to the external form of a completed reproducing stylus or approximate to said external form. Then an ion is implanted through different directions E, F and G directing toward a part including the area where the electrode based on material S is expected to form in such an amount that does not convert the diamond of material S into low resistance with the ion implanted from an individual direction among specified plural directions. Thus an electrode part is formed by a layer A having low resistance converted highly into graphite only at the area where the electrode part of the material S is expected to form.

Description

[Detailed Description of the Invention] An information recording medium disc having a recording trace formed by arranging bits corresponding to an information signal in a spiral or concentric form, slidingly contacting the recording trace, A capacitance change detection reproducing needle equipped with an electrode part that can read information and information signals from a disc as changes in capacitance value is used to read information signals from a disc. Information recording and reproducing systems that detect changes in capacitance have superior features compared to optical and other types of information recording and reproducing systems, and research into their practical application has been promoted. It has now reached the stage of practical application.

By the way, in the information recording and reproducing method that detects changes in capacitance value, when reading information signals from the disk,
Whether the disk has a guide groove (Fig. 1 (Fig. 81)) or does not have a guide groove (Fig. 1 (Fig. b1), either form Even if the disc is of a type, a playback stylus is required that is used in sliding contact with the disc surface, but the playback stylus gradually wears out due to sliding contact with the disc surface during playback operation, so it cannot be used over a long period of time. Regenerative needle that can be regenerated (long-life regenerative needle)
In order to obtain this, it is a matter of course that a high hardness material having wear resistance (high hardness wear resistant material) must be used as the material for the regenerated needle.

Figures 1(a) and 1(b) are perspective views of an example of a regeneration needle that detects changes in capacitance.
).

In the figure (b), 1 is a regenerated needle body made of a high-hardness material having wear resistance, 2 is a sliding contact surface, and 3 is an electrode adhered on the electrode adhesion forming surface. The capacitance change detection type reproducing needle detects the information signal in the recorded trace by the end of the electrode 3 that is in sliding contact with the disk surface while its sliding surface 2 is in sliding contact with the surface of the disk D. Since the regeneration operation is performed by reading out changes in the capacitance value, in order for the regeneration operation to be performed well by the regeneration needle, the end portion of the electrode 3 attached to the electrode attachment forming surface of the regeneration needle main body 1 must be must always be present on the sliding contact surface 2, and for this purpose, it is necessary to form a wear-resistant electrode with great adhesion strength on the electrode adhesion forming surface. Needed.

Therefore, for a long-life capacitance value change detection type regenerated needle, a high hardness material with wear resistance is used as the material for the regenerated needle body, and the electrode attachment surface of the regenerated needle body is What is required is an electrode with a high adhesion strength and wear resistance.
Diamond is well known as a highly hard material with wear resistance, but it is difficult to attach wear-resistant electrode materials to it with a high adhesion strength. When making a regeneration needle that detects changes in capacitance value, a conductive material that exhibits relatively high adhesion strength with diamond is selected as the electrode material, and a conductive film is deposited. Alternatively, as shown in Japanese Utility Model Application Publication No. 55-28289, methods have been adopted in which ions of a conductive substance are injected into diamond by ion implantation to form a conductive layer. .

However, by using a conductive material such as hafnium or titanium, which has a relatively high adhesion strength with diamond, the electrode adhesion forming surface of the regenerated needle body made of diamond is used. Even if a conductive thin film is deposited and formed by a so-called dry plating method such as vapor deposition method, sputtering method, or ion blating method, it is not possible to obtain an electrode with sufficiently satisfactory wear resistance. In addition, in the case of regenerated needles in which the electrodes are constructed by attaching a thin film of metal such as titanium or hafnium to diamond using the dry plating method, since the electrode 3 is a soft metal, it is difficult to use the regenerated needle. If the end of the electrode is worn out, resulting in the condition shown in Figure 2 (a), or because the metal of the electrode melts at a relatively low temperature, it may occur during use of the recycled needle. As a result of the electric discharge generated between the electrode and the disk D, the electrode was damaged as shown in FIG. 2(b), making it difficult to obtain a regenerated needle with a long life.

When forming an electrode part with a desired electrical resistance value, the implantation of a large amount of ions to form an electrode part with the required electrical resistance value causes lattice defects in the diamond crystal and makes the diamond brittle, so regeneration is required after ion implantation. When polishing is performed on the back surface of the needle body (the surface adjacent to the electrode attachment surface), the diamond 7' diamond may be chipped as shown in FIG. 2(C).

In other words, when forming the electrode 3 by implanting ions into the diamond surface on which the electrode is to be formed in the material of the regenerated needle body, a large amount of ions are implanted into the surface of the diamond on which the electrode is to be formed, and at the same time the electrode is formed. Since a large amount of ion implantation has also been performed on the back surface adjacent to the planned surface, the electrical resistance value of the back surface has also decreased, and as it is, the electrode 3 with the required electrode width can be provided. It is not possible to obtain regenerated needles. Therefore, in order to obtain a recycled needle in which the electrode 3 exhibiting the required low electrical resistance value is formed only on the surface of the diamond where the electrode is planned to be formed, it is necessary to polish the back surface of the diamond after ion implantation into the diamond is completed. Although it is necessary to perform processing to remove the conductive layer formed on the back side, it is necessary to remove the conductive layer formed on the back surface of the diamond in a state where the electrode 3 that exhibits the required low resistance value is formed on the diamond by ion implantation. Since crystal lattice defects occur in the diamond, the polishing process on the back surface causes chips as shown in FIG. 2(C) in the diamond. □The present invention provides a long-life recycled needle even if the recycled needle is constructed by attaching the electrode 3 to the diamond electrode formation surface of the recycled needle body using the so-called dry plating method described above. The ion implantation method solves the above-mentioned problems that occurred when attempting to form an electrode part in diamond by implanting ions into diamond using the ion implantation method. The purpose of this invention is to provide a method for manufacturing a capacitance value change detection type regenerated needle, which enables easy mass production of regenerated needles by the method. The specific details of the manufacturing method of the value change detection type regeneration needle will be explained in detail.

First, in Figure 3, argon ion Ar+ is applied to the diamond.
2 is a chart showing the relationship between the dose and the sheet resistance value of the diamond surface when ions are implanted at an accelerating voltage of 150 KV and an ion current of about 150 μ.

The sheet resistance value of the surface of diamond rapidly decreases as the dose increases, but this phenomenon appears with the same tendency regardless of the type of element. The above-mentioned sheet resistance value of the diamond surface is determined by the degree to which the diamond is graphitized by ion implantation.

Furthermore, LSS theory has revealed that when ions are implanted into diamond, the positions where the implanted ions stop exhibits a Gaussian distribution from the surface of the diamond to the inside of the diamond. When calculating the stopping position of ions when Ar+ ions are implanted into diamond at an accelerating voltage of 150 KV, a chart as shown in FIG. 4 is obtained. In FIG. 4, the horizontal axis represents the distance from the diamond surface, and O on the horizontal axis indicates the diamond surface. Further, the vertical axis in FIG. 4 indicates the number of ions per unit volume (ion implantation density).

From Figure 4, when argon ions Ar+ are implanted into the diamond at an accelerating voltage of 150 KV, the maximum number of ions implanted is approximately 750 angstroms from the surface of the diamond. As you can see, when ions are implanted into a diamond, the graphitization that occurs in the diamond is small on the surface of the diamond, and the graphitization occurs slightly inside the diamond from the surface. It shows a two-layered structure in which there are areas with advanced chemical formation.

When ions are implanted into a diamond to turn it into graphite and create a part with a low electrical resistance value that can be used as an electrode part, the electrode part shows the required electrical resistance value. Ion implantation must be performed at a dose that will yield a desired result, but if ion implantation is performed at such a dose, not only the area where the electrode will be formed in the regenerating needle body but also the back surface. Since the electrical resistance value of the portion also decreases, after ion implantation, the back surface portion must be polished to remove the portion where the electrical resistance value has decreased, and As mentioned above, there are problems such as the diamond being chipped in this case.

The present invention is characterized in that at least the portion of the sliding surface of the regenerated needle and the portion where the electrode portion is to be formed are formed of the diamond material, and the outer shape of the regenerated needle is completed. Prepare a material for the recycled needle body that has been processed in advance so that it has the same external shape as the shape or the external shape of the completed recycled needle, and plan to form the electrode part in the material for the recycled needle body described above. By implanting ions from a plurality of six different directions toward the part including the part, and from one direction in each of the six different directions, the resistance of the diamond in the material of the regenerated needle body is reduced.
By implanting ions in such an amount that the needle body is made of diamond, the electrode part is formed only in the part where the electrode part is to be formed in the diamond, which is the material of the regenerated needle body. This made it possible to solve the above-mentioned problems.

FIG. 5 is a plan cross-sectional view of the material of the recycled needle body for explaining the manufacturing method of the capacitance value change detection type refill according to the present invention, and (a) to (d) in FIG. In the figures, one material S of the regenerated needle main body having six different cross-sectional shapes is shown.

In each of Figures 5(a) to (d1), arrows E and F
.

G is an arrow indicating the direction of ion implantation into the material S of the recycled needle body, and in FIG. However, in carrying out the method of the present invention, the material S of the regenerated needle body is irradiated from six different directions toward the portion including the portion where the electrode portion is to be formed. By implanting ions from one direction in each direction, the amount of ion implantation is such that the resistance of the diamond in the material of the regenerated needle body is not reduced, and as a result, As a result, the electrode portion may be formed only in the portion of the diamond of the material S of the regenerated needle body where the electrode portion is to be formed by a low-resistance layer with advanced graphitization.

The ion implantations to be performed from the six different directions E, F, and G in FIGS. 5(a) to (d1) may be performed simultaneously, or the ion implantations from each direction may be It may also be performed sequentially on the axis.

The ions to be implanted may be of any element, but for example, Ar+Li, B+C+N+Ne+P+
S! .

Ions of elements such as sb can be effectively used.

Here, an example of a case where argon ions Ar are injected to form an electrode part in the material of the regenerated needle body is shown.
xl O15/ad in each direction E', F
When argon ions are implanted into the material S of the regenerated needle body every Ar+ is injected.

Then, in the diamond in the material S of the regenerated needle body, a region A- is created where argon ions Ar+ implanted from six different directions E, F, and G overlap, and in that region A, graphitization progresses and the A low resistance layer A having a resistance on the order of 10 −2 Ω is formed in the portion.

The low-resistance layer A formed inside the diamond in this way is surrounded by less graphitized diamond, so the low-resistance layer A described above can be used as an electrode part. A regenerated needle made in the above manner will have a long lifespan with the electrode portion well protected. In addition, in the regenerated needle made according to the present invention, since the amount of ion implantation into the portion other than the portion where the electrode is planned to be formed is small, the electrical resistance value in the portion other than the portion where the electrode is planned to be formed can be made extremely high.
Therefore, when manufacturing a recycled needle by the method of the present invention, it is not necessary to perform polishing on the back surface after the ion implantation/implantation process for forming the electrode part. The diamond near the electrode part will not be chipped during manufacturing.

Next, in the case where it is necessary to form an electrical connection part to the electrode part made of the low resistance layer A formed in the diamond of the material S of the regenerated needle main body as described above, The connection can be made as follows□.

・　・、1:.

That is, in FIG. 6, A is the electrode portion made of the low resistance layer A formed inside the diamond as described above, and the connection portion J for electrical connection with this electrode portion is , the area between the surface of the diamond and the electrode in that area can be locally graphitized to lower the resistance of that area. A
r” at a low accelerating voltage such as 50KV.
This can be achieved by progressing the graphitization of the /i portion.

In FIG. 6, reference numeral 4 denotes the base of the regenerated needle body made of a metal rod such as a titanium rod, and the base 4 and the diamond are welded using metal solder or the like.

As is clear from the above description, in the manufacturing method of the capacitance value change detection type regenerated needle of the present invention, a plurality of portions of the material of the regenerated needle body, including the portion where the electrode portion is planned to be formed, are formed. By implanting ions from 6 different directions, one of each of the 6 different directions, the ion implantation is performed in such an amount that the resistance of the diamond in the material of the regenerated needle body is not reduced. Since the electrode part is formed in the diamond by the process, the problems of the conventional method mentioned above do not occur, and recycled needles can be easily mass-produced. The connecting portion can also be easily configured, and the method of the present invention makes it possible to easily provide a regenerated needle with a long life.

[Brief explanation of the drawing]

Figures 1(a) and (b1) are perspective views of regenerative needles that detect changes in capacitance, and Figures 2(a) to (e) are perspective views of regenerative needles that detect changes in capacitance. A perspective view of the needle, FIGS. 3 and 4 are explanatory charts, FIGS. 5(a) to (d1) are plan sectional views of the regenerated needle, and FIG. 6 is a perspective view of the regenerated needle. ... Disc, A ... Low resistance layer, J ... Connection part. 1 ... Regeneration needle body, 4 ... Base (b) Coracoid

Claims (1)

[Scope of Claims] l At least the portion of the sliding surface of the regenerated needle and the portion where the electrode portion is to be formed are made of diamond material, and the outer shape of the regenerated needle is completed. The shape is the same as the shape, or close to the shape of the completed regenerated needle (・
A pre-processed material for the regenerated needle body is prepared, and the material for the regenerated needle body is examined from six different directions toward the portion of the material for the regenerated needle body that includes the portion where the electrode portion is to be formed. By implanting ions in such an amount that the resistance of the diamond in the material of the regenerated needle body will not be reduced by implanting ions from one direction in each direction, the material of the regenerated needle body can be improved. Method 2 of manufacturing a regenerated needle that detects changes in capacitance value, in which an electrode portion is formed by a low-resistance layer with advanced graphitization only in the area where the electrode portion is planned to be formed in the diamond. The sliding contact surface part and the part where the electrode part is to be formed are made of the diamond material, and the external shape is the same as that of the completed recycled needle, or the completed recycled needle. A recycled needle body material that has been processed in advance so as to have an external shape close to that of the needle is prepared, and a plurality of six different shapes are prepared toward the portion of the recycled needle body material described above that includes the portion where the electrode portion is to be formed. By implanting ions from each of the six different directions, the resistance of diamond, which is the material of the regeneration needle body, will not be lowered. By doing this, the electrode part is formed by a low resistance layer with advanced graphitization only in the part where the electrode part is planned to be formed in the diamond of the material of the regenerated needle body, and the smudges near the base of the electrode part are removed from the diamond. A method for manufacturing a regenerated needle that detects changes in capacitance value by forming a graphitized low-resistance layer from the surface to the electrode part.