JPS5836908A - Manufacture of magnetic body of thin nitride film - Google Patents

Abstract

PURPOSE:To manufacture a magnetic body of a thin nitride film with superior magnetic characteristics, wear resistance and corrosion resistance by forming a thin film of a magnetic metal or alloy by a vapor deposition method while introducing nitrogen into the metal or alloy and by converting the resulting thin nitride film into an amorphous compound. CONSTITUTION:A magnetic metal such as Fe, Co or Ni or an alloy thereof in a crucible 3 set in a vacuum vessel 1 is melted and evaporated with an electron beam generating filament 2. At the same time, gaseous nitrogen is fed to the vessel 1 through a needle valve 4 until the vacuum degree gauged with a vacuum gauge becomes 5X10<-4>Torr. Thermions are emitted with filament 6 and an electrode 7 to excite and ionize the gaseous nitrogen atoms and the evaporated magnetic metal. At this time, by applying about 200V negative voltage to a polyimide film substrate 8 placed in the vessel 1, said metallic ions and nitrogen ions are accelerated and hit on the substrate 8 to deposit an amorphous thin metallic nitride film. Thus, a magnetic body is manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a nitride thin film magnetic material having excellent wear resistance, corrosion resistance, and high magnetic properties.

Generally, methods for producing thin films made only of magnetic metals and their alloys, such as Fee COI N1, include methods such as vapor deposition in a vacuum or filtering. The thin film produced by this method has the same crystal structure as a solid (bulk) metal body, and its magnetic properties are almost the same as the bulk body. When used in a closed position, there are problems in terms of wear resistance and corrosion resistance, which poses a major obstacle to practical application.

Recently, nitride magnetic materials with a crystalline structure have excellent magnetic and mechanical properties. For example, in the case of Fe, metal pe
The powder was heated in ammonia gas and hydrogen gas for 400″c-s.
A method has been proposed in which nitride powder is produced by processing at a temperature of oooC and then applied thinly to form a thin film.
The thin film produced by the above method has a limited composition ratio of FC and N, and has a saturation magnetization of 160 emu/gr l! ! Only F%N with a face-centered cubic lattice structure of 100% can be obtained, and it is not possible to produce a material with a high F content, which is expected to have a higher saturation magnetization. .

As a result of various studies on the production of nitride thin film magnetic materials that have excellent magnetic properties, wear resistance, and corrosion resistance at the same time, the Ministry of the Invention has decided to produce thin films of magnetic metals or their alloys by vapor deposition. By incorporating a certain amount of nitrogen into the metal or alloy and making the nitride thin film an amorphous compound, it has excellent magnetic properties such as saturation magnetization, coercive force, and magnetic permeability, as well as good wear resistance. It was found that corrosion resistance can be obtained.

This invention melts and evaporates a magnetic metal or its alloy in a vacuum chamber, and at the same time increases the degree of vacuum to I x 10.
Nitrogen gas corresponding to ~l This is a method for producing a nitride thin film magnetic material, the gist of which is to produce an amorphous compound of a nitrogen-containing magnetic metal or its alloy by collisional adhesion to the magnetic material.

The features of this invention are (1) that the amount of nitrogen contained in the metal or alloy can be freely controlled, (2) that a thin film with an amorphous tank structure can be obtained, and that these can be obtained at the same time.

In this invention, the amount of nitrogen in the metal or alloy vapor can be adjusted by employing a needle valve for introducing nitrogen gas, and the amount of nitrogen in the formed thin film can be adjusted. In this case, the reason for specifying the equivalent degree of vacuum when introducing nitrogen gas is that the degree of vacuum is I
If nitrogen gas exceeding When the characteristic is lost and the amount of nitrogen increases compared to Fe2N, for example, the saturation magnetization becomes Zoo ~B□emn
/gr, which is undesirable as it approximates an oxide magnetic material. Furthermore, when the degree of vacuum is increased to less than 1×10''I'orr, there is no detectable nitrogen in the formed thin film and no amorphous structure is obtained. In the case of , the amorphous nitride with nitrogen amount equivalent to FeeN and FeaN is
The amount of production is greatest when it is equivalent to I'orr.

Next, in order to obtain the amorphous structure described in (2) above, the nitrogen introduced into the vacuum chamber and the evaporated metal are excited into an ionic state by thermoelectrons or the like. As a method for ionization, in addition to using thermoelectrons as described above, it is also possible to collide with ionized inert gas, but it is preferable to use thermoelectrons to avoid contamination with impurities. Further, the amount of ionization can be adjusted by electrical input, and the amount of ionization depends on the amount of gas introduced and ξ, which adjusts the amount of nitrogen contained in the magnetic metal.

Next, these ionized metals or their alloys and 1
Applying an electrostatic field of 50 to 5 oovs to elementary atoms,
Collision adhesion onto a substrate provided in a vacuum chamber. In this case, non-ionized metal or alloy and nitrogen atoms also adhere to the substrate at the same time, but the strength of the applied electric field is an important factor for adjusting magnetic properties, crystal structure, etc.

In this invention, the process by which a compound with an amorphous structure is generated is, for example, in the case of Fl-N, ionized F* clusters and nitrogen ions are strongly combined to form F*! on the substrate. N
(x is any positive number) is formed, and accelerated ye or N ions react violently with N or F atoms on the substrate to form nitrides4. , Fes N g F"4 N p Fex
A compound with a clear composition and crystal structure like N is not formed on the substrate, but becomes amorphous, resulting in a thin film magnetic material that has the same hardness, wear resistance, and corrosion resistance as other amorphous alloys. It will be done.

Embodiments of the present invention will be explained below with reference to the drawings.

In Figure 1111, metal iron with a purity of 99% is melted and evaporated in a metal melting crucible (3) using an electron beam generating filament in a vacuum chamber (1), and then nitrogen gas is passed through a needle valve (4). , introduced ionization vacuum needle (!I)
The flow rate of nitrogen gas was adjusted so that the degree of vacuum at The nitrogen atoms and a portion of the evaporated PE are excited and ionized. The amount of thermoelectrons generated can be monitored by the current value between the filament (6) and the electrode ().

Next, a negative voltage of 200V 1 degree is applied to the polyamide film substrate + 11 Iζ to accelerate the PC and nitrogen ions, causing them to collide and adhere to the substrate.
Amorphous iron nitride is deposited at a rate of /sec. In this invention, the amount of nitrogen contained in PE is determined by the deposition rate and the amount of nitrogen inflow.

The amorphous iron nitride on the polyamide turf film produced by the above method and having a thickness of 3 meters was cut to an appropriate size, and the magnetization was measured using the magnetic needle number of the sample vibrating rack.

The results are shown in FIG.

As is clear from the hysteresis loop in Figure 82, this invention has shown that amorphous iron nitride has an extremely large saturation magnetization close to that of pure iron, and is superior to crystalline iron nitride (Fe, N). I understand.

FIG. 3 shows the results of investigating the crystal structure of crystalline F@14N and the amorphous nitride according to the present invention by xIII analysis. Figure 3 (6) shows the diffraction line of the crystalline nitride, and Figure 3 shows the decoupling line of the amorphous nitride of the present invention. It is clear that it is an amorphous facultative body.

Next, a scratch hardness test was conducted on the thin film deposited on a smooth glass substrate under the same conditions as in the above example, and the results showed that the thin film of the present invention A decrease in the scratch paper width was confirmed, and as for corrosion resistance, as a result of a 5,000 hour durability test under saturated steam at 40°C, the PE thin film produced by normal vapor deposition was oxidized and was chemically and magnetically oxidized. has also become completely different, but ξ
No change was observed in the amorphous nitride thin film of the invention.

According to the present invention, it is possible to select a magnetic metal or alloy suitable for the purpose of obtaining an electrified magnetic thin film having characteristics of saturation magnetization, coercive force, and magnetic permeability, and to use it as a magnetic recording medium material and a magnetic head material. This is a very efficient method for applying.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an implementation device in an embodiment of the present invention;
FIG. 2 is a graph showing the magnetization curve of the nitride thin film according to the present invention, and FIG. 3 is a graph showing the xI1 diffraction Bakun. This is the case. In the figure, 1--vacuum chamber, 2--electron beam generating filament, 3--metal melting crucible, 4--secondary valve, 5--
・・Ionization vacuum gauge, 6-・Filament, 7-・Electrode, 8
···substrate. Applicant: Sumitomo Special Metals Co., Ltd. Agent Shin 1) Ryo Figure 1 Figure 2 Takashi 7σ (emu/gr1 Figure 3 (α) !I4 degrees (deg) (b) Angle (deg)

Claims (1)

[Claims] At the same time, the magnetic metal or its alloy is melted and evaporated in a vacuum chamber, and the vacuum level is reduced to 'IXIG''~10.
Nitrogen gas equivalent to 'forr is introduced into the vacuum chamber described above, ionizes the evaporated metal or its alloy and nitrogen, and then applies an accelerating voltage to the ionized atoms to form a layer on the substrate inside the chamber. 1. A method for producing a nitride thin film magnetic material, which is characterized by producing an amorphous compound of a nitrogen-containing magnetic metal or an alloy thereof by collision adhesion to a magnetic material.