JPS6038002B2 - thermal head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermal head having a thin film heating resistor made of a metal shelving material and carbon, and also to a method for manufacturing the same.

A thermal head used for thermal print recording includes a plurality of heating resistors on a substrate having electrical insulation and a smooth surface, such as glass, and an electric conductor for supplying power to the heating resistors. Recording is performed by applying a current to the corresponding heat-generating resistor through an electric conductor to generate heat so as to obtain a necessary thermal pattern according to the information to be recorded, and bringing the heat-generating resistor into contact with the recording medium. Heat generating resistors used therein include conventional thin film heat generating resistors such as tantalum nitride and dichrome tin oxide, thick film heat generating resistors using silver-palladium, etc., and semiconductor heat generating resistors using silicon semiconductor. Among these, thermal heads using thin film heating resistors have better thermal response, superior heat resistance and thermal shock resistance, longer lifespan, and higher reliability than thick film heating resistors, semiconductor heating resistors, etc. It has the following characteristics. Conventionally, tantalum nitride has been used as a thin-film heating resistor because it has excellent heat resistance, high reliability, and has a relatively high specific resistance value of 250 to 300 French ○, and has good manufacturing controllability. It is used. However, tantalum nitride is rapidly oxidized at high temperatures of about 300 qo or higher, resulting in a rapid increase in its resistance value, which has the disadvantage of deteriorating print density when printing on recording paper.

First, to compensate for this drawback, silicon oxide (Si02
) is provided with an oxidation-resistant protective layer of tantalum oxide (T
A2Q) was provided with a wear-resistant layer and used as a thermal head, but the change in resistance when the thermal head was driven for a long time was still not fully satisfactory. In particular, in recent years, the demand for high-speed thermal heads has increased, so it is necessary to shorten the energizing pulse of the head to color the thermal paper, which means that the power consumption is higher than before.
Since the heating resistor becomes even hotter, its life becomes shorter. Therefore, there is a demand for a heating resistor with even higher heat resistance. Also, the sheet resistance of tantalum nitride is usually 50
It is around 0/mouth, and even if it is made especially large as a thermal head, it is about 1000/mouth.In order to further increase the resistance value, methods such as trimming or thinning the film are used, but in this case, the manufacturing process However, there are drawbacks such as the process becomes complicated and the service life is adversely affected.

As described above, the tantalum nitride thin film heating resistor cannot have a large sheet resistance, so in order to supply enough power to heat the resistor, a large current is inevitably required, and the resistance value of the electric conductor becomes a problem.

In other words, since the resistance value of the electrical conductor cannot be ignored compared to the resistance value of the thin-film heating resistor, the amount of heat generated by each resistor will differ due to the difference in the distance between each electrical conductor connected to the resistor, and the recording Differences in density occur in the pattern, resulting in poor recording quality. Furthermore, if the size of the thin film heating resistor is reduced in order to increase the recording density, the sheet resistance value of the thin film heating resistor remains unchanged and only the resistance value of the electrical conductor increases, so power consumption in the electrical conductor becomes a problem. Furthermore, if the thickness of the electrical conductor is made extremely large in order to avoid this, in the case of multi-layer wiring, the surface becomes extremely uneven and becomes susceptible to abrasion, resulting in major structural problems. Also, if the current is large, it is a heating power source,
Inconveniences also arise, such as the need to increase the capacity of switching circuits and the like. The present invention improves the above points and provides a thermal head using a thin film heating resistor that is resistant to oxidation, has a stable resistance value, and allows the specific resistance to be selected up to a high value.
Its feature lies in the heating resistor made of metal oxide and carbon.

In this heating resistor, metal shelving and carbon coexist on an atomic scale. A detailed description will be given below with reference to the drawings.

FIG. 1 is a sectional view of a main part of an example of the shape of a thermal head applied to the present invention. 1 in the figure is a substrate made of an electrical insulator such as ceramics, glass, or glazed ceramics. 2 is a thin film heating resistor according to the present invention, which is made of a metal shelf and carbon.

Reference numeral 3 denotes an electric conductor for supplying power to the thin film heating resistor, which is made of a good electric conductor such as aluminum or gold.

4 is a protective layer for the thin film heating resistor and electric conductor, for example, a multilayer structure made of silicon oxide, magnesium oxide, aluminum oxide, tantalum oxide, or a combination of these, manufactured by electron beam evaporation, sputtering, etc., is used. The life of the thermal head can be further extended. The thin film heating resistor of the present invention made of a metal lateral oxide and carbon can be manufactured by either sputtering or electron beam evaporation. There are a method of sputtering a target, a method of using a shelf element and a metal as a target at the same time, a method of performing active sputtering using only a metal as a target in an atmosphere containing argon, methane, and diporane. When using a metal shelving object as a target, it can be used as a target by placing the metal shelving object in a powder state or pressed state on a quartz plate, for example, but it is possible to use it as a target by placing the metal shelving object in a powder state or a pressed state on a quartz dish, etc. It is easier to control sputtering if a target is used.

In addition, when targeting a shelf element and a metal at the same time, it can be carried out by combining the shelf element and the metal, or by embedding one in the other or arranging one on a part of the surface. In either case, 1 × 10-Torr ~ 5 × lo-ITor
It is best to carry out in a mixed atmosphere of argon and methane,
Preferably 1×10-2Ton to 1×10-ITorr
Good.

In addition, targeting single metals, argon, methane,
When performing active sputtering in a mixed atmosphere of diborane, the total gas pressure is 1 x 10-Ton to 5 x 10-ITor.
r, preferably 1 x 10-2 Tom to 5 x 1 geb orr
, in which the partial pressure of diborane is 1 to 10%, preferably 2 to 6% of the total pressure.

During any of the above sputtering processes, by selecting the methane partial pressure in the atmosphere from 0.1 to 10%, carbon is added to the heating resistor at an atomic ratio of 0.00% of the total amount of metal.
5 or more can be contained. If the carbon content is too low, it will not be effective, and if it is too high, it will be difficult to control the specific resistance and the heat resistance will deteriorate, so it should be 0.01 to 0.5 of the total metal content.
(atomic ratio) is appropriate. The specific resistance value of the heating resistor thus prepared can be selected from 100 degrees Q to 5000 degrees. When manufacturing a heat generating resistor by electron beam evaporation, a tablet is made by pressing powder of metal shelving at a pressure of about 100 k9/m or more, and the tablet size is 1×10-4 Tom.
Vapor deposition can be performed on a substrate that has been kept at a constant temperature in advance at a high degree of vacuum. At this time, by introducing a gas containing methane into the electron beam evaporation process using a needle valve or the like, the nitrogen content in the heating resistor is reduced to zero based on the total amount of metal.
．． 005 to 0.5 (atomic ratio). The thin film heating resistor created in this way is made of metal shelving and carbon (however, it contains impurities such as ○ and N), and if the specific resistance value is set high, the resistance value of the electrode part may be high to some extent. The manufacturing process becomes easier, and by making the electrode thinner, surface irregularities are reduced and wear resistance is improved.

In addition, since the voltage drop at the electrode portion is negligible, uneven color density due to uneven heating of the thin film heating resistor is also reduced, and electrode patterns such as matrix wiring can be designed more freely. Furthermore, by heating the substrate to 200 DEG C. to 50 DEG C. during sputtering or electron beam evaporation, the adhesion between the substrate and the thin film heating resistor is improved, which is effective in improving the stability of the film.

Here, the metal shelving is a magnetized substance such as hafnium, zirconium, lanthanum, titanium, tantalum, tungsten, molybdenum, niobium, chromium, vanadium, etc., and it is also possible to use them alone or in a mixture of two or more types. .

In addition to the method described above, the heating resistor of the present invention made of metal shelving and carbon can be manufactured by forming a mixture of metal shelving and conductive carbide into a target or tablet, and then manufacturing it by sputtering or electron beam evaporation. As the conductive carbide, one or a mixture of two or more of nitrides such as hafnium, zirconium, lanthanum, titanium, tantalum, tungsten, molybdenum, chromium, niobium, and vanadium can be selected.

Next, an explanation will be given based on an example.

(Example 1) A well-cleaned glazed alumina substrate with a glass thickness of 50 mm was heated using a 5-inch diameter shelved zirconium (Z) target hot-pressed at 1100 mm.
Argon pressure 4×10°C while heating the substrate to 00°C
rr, methane pressure of 3×10-3 Ton, and high-frequency bipolar sputtering in a mixed gas atmosphere.

The sputtering rate was 200A/min, and the input power was 3. After skin/eye sputtering for 5 minutes, a thin film heating resistor with a film thickness of 1000Δ was obtained. The specific resistance was 900 French skin, and the area resistance was 900/mouth. When the composition of this film was examined using an ion microanalyzer, carbon was found to be 0.2% of zirconium.
It contained 5 (atomic ratio). On top of this, titanium 10A and aluminum were deposited by lAm electron beam evaporation, and a thermal head pattern having a resolution of 4 lines/side was formed by selective etching, and this was designated as thermal head A. Furthermore, 1 meter of silicon oxide (Si02) was added as a protective layer on top of this.
A mirror layer of 10 m of tantalum oxide (Ta2Q) was continuously formed by sputtering to form a thermal head. For comparison, tantalum was targeted by high-frequency bipolar reactive sputtering, and the total pressure of argon and nitrogen was 8 x 10-2To.
n, 1000 at a nitrogen partial pressure of 1 x 10-4 Torr.
Thermal head B was made of a chambered tantalum thin film heating resistor having a thickness of A. This tantalum thin film heating resistor had a specific resistance of 260 rQ arc and an area resistance of 260/hole. Thermal head B is further coated with lAm of silicon oxide (Si02) and tantalum oxide (Ta2) as a protective film.
05) was continuously laminated for 10 m by sputtering to form a thermal head &. For these thermal heads, 5
An acceleration test was performed while increasing the power of the 8hs square wave at 0HZ by lw/fence every 30 minutes.

The results are shown in FIG. As is clear from the figure, it was found that the thermal head having the thin film heating resistor produced by the manufacturing method according to the present invention could withstand high applied power and had little change in resistance at high temperatures. In other words, while it is surprising that the comparative example can be used without a protective film, the thermal head according to the present invention can be put into practical use without a protective film, and when a protective film is attached, very good heat resistance can be obtained. Ta. (Example 2) Using a 6-inch-diameter shelved hafnium (Hf&) target hot-pressed at 1300 qo, a thoroughly cleaned glazed alumina substrate with a glass thickness of 50 mm was heated to 20 mm.
Heating the substrate to 0.000C and argon pressure of 4
High frequency bipolar sputtering was performed in a mixed gas atmosphere with a methane pressure of 4×10 −3 Torr.

The sputtering rate was 200A/min, and the input power was 3. After sputtering on skin/meat for 3 minutes, a thin film heating resistor of the present invention having a film thickness of 600A was obtained. The specific resistance was 1800〃○ skin, and the area resistance was 3000/mouth. 1 vanadium on top of this
0A, aluminum was applied by electron beam evaporation for 1 meter, a thermal head pattern with a resolution of 4 lines/fence was formed by selective etching, and on top of this, silicon oxide (Si02) was added as a protective layer for 21 meters, and aluminum oxide was deposited for 21 meters. (N2
03) was continuously laminated to a thickness of 5 mm by sputtering to create a thermal head. Example 1 for this thermal head
When we conducted the same acceleration test as the thermal head, we obtained results similar to those of the thermal head.

(Example 3) A well-cleaned glazed alumina substrate with a glass thickness of 50 m was heated at 400°C using a 6-inch diameter shelved lanthanum (La&) target hot-pressed at 130 mm.
The substrate was heated, and high-frequency bipolar sputtering was performed in a mixed gas atmosphere with an argon pressure of 3×10 -3 tons and a methane pressure of 2×10 -3 tons.

The sputtering rate was 150A/min, and the input power was 3. When sputtered on the skin/eye for 5 minutes, a thin film heating resistor of the present invention having a film thickness of 750Δ was obtained. The specific resistance was 2,600 French○, and the area resistance was 350Q/□. Titanium 10A on top of this
, aluminum was applied by electron beam evaporation, and a thermal head pattern with a resolution of 4 lines/side was formed by selective etching, and on top of this, silicon oxide (Si02) was added as a protective layer with 2 m, and magnesium oxide ( Mg0)
A thermal head was fabricated by sputtering continuously for 5 km. When this thermal head was subjected to the same acceleration test as in Example 1, results similar to those of the thermal head were obtained.

Instead of LaB6 in this example, CrB, TiB2, Nb
Almost similar results were obtained using B2, WB, MOB, and VB2.

(Example 4) Titanium shelving (TiB2), tantalum shelving (TaB2), niobium shelving (NbB2), tungsten shelving (WB), molybdenum shelving (MOB), chromium shelving (CrB2) as metal shelving materials , shelved vanadium (V year) was selected and an equal amount of each of these powders was placed on a 5 inch diameter quartz blood as a target.

Sputtering was performed using these targets under the same conditions as in Example 1 to produce a heating element with a film thickness of 1000A. On top of this, 30 m of titanium and 1.5 m of aluminum
After depositing with an electron beam, a thermal head with a resolution of 4 ribs was created by selective etching. Furthermore, 3 rms of silicon oxide and 6 rms of tantalum oxide were laminated as protective layers on the thermal head by sputtering. When these thermal heads were subjected to the same accelerated test as in Example 1, all of them had much better heat resistance than conventional thermal heads using tantalum nitride.

(Example 5) After uniformly dispersing 50 mol% of magnetized zirconium (ZrB2) and 50 mol% of shelved hafnium (Hf&), 1
It was hot pressed at 200q0 to form a target with a diameter of 6 inches.

Using this target, thoroughly cleaned glass thickness 5
A glazed alumina substrate with a diameter of 0 m is heated to 30,000 ℃, an argon pressure of 4 x 10-orr, and a methane pressure of 1
High frequency bipolar sputtering was performed in a mixed gas atmosphere of ×10-3 Torr. The sputtering rate was 150A/min, and the input power was 3. When sputtered on skin/ground for 6 minutes, 9
A thin film heating resistor with a film thickness of 00A was obtained. The specific resistance is 5
The area resistance was 600/mouth. On top of this, titanium 10A and aluminum were deposited by electron beam evaporation for 1 m, a thermal head pattern with a resolution of 4 arms/arm was created by selective etching, and silicon oxide (Si02) was added as a protective layer on top of this. m, tantalum oxide (
A thermal head was created by continuously laminating Ta205) for 10 rms by sputtering. When this thermal head was subjected to the same acceleration test as in Example 1, results similar to those of the thermal head were obtained.

(Example 6) Zirconium shelving (ZrB2) and titanium shelving (TiB2)
) and shelved lanthanum (La&) were uniformly mixed in a molar ratio of 2:1:1, and a powder was placed on a 5-inch diameter quartz blood and used as a target.

Sputtering was performed using these targets under the same conditions as in Example 1 to produce a heating element with a film thickness of 1000A. On top of this, 30 m of titanium and 1.5 m of aluminum
After electron beam deposition, a thermal head with a resolution of 4 wires/willow was created by selective etching. Further, as a protective layer for the thermal head, 3 mm of silicon oxide and 6 mm of tantalum oxide were formed by sputtering.

When this thermal head was subjected to the same acceleration test as in Example 1, very good heat resistance was obtained compared to the conventional thermal head using tantalum nitride.

(Example 7) A target in which a large number of phosphorized boron plates with a diameter of 1'4 inches were placed on a tantalum metal plate with a diameter of 6 inches so that the surface area ratio of tantalum metal to lateralization was approximately 1:2. was used.

500 thoroughly cleaned glazed ceramic substrates
Heating the substrate to qo and argon pressure: 3×10-2Ton,
At a methane pressure of 2×1 orr, R. F. Sputtering was performed using two electrodes. When sputtering was carried out for 8 minutes at a sputtering rate of 100 A/min, a thin film heating resistor with a film thickness of 800 A, a specific resistance value of 1050 peaks and arcs, and an area resistance of 130 cm was obtained. After depositing titanium on this with a 10A electron beam and aluminum with a 1F electron beam, a thermal head pattern with a resolution of 4 lines/Yanagi was formed by selective etching. Next, 10 mm of magnesium oxide (Mg0) was deposited as a protective film by sputtering. When this thermal head was subjected to the same acceleration test as in Example 1, the resistance change rate was within 2% up to 2 fences, which was a very good result compared to the thermal head using tantalum nitride. was gotten.

(Example 8) A 6-inch diameter metal zirconium plate was used as a target.

400 thoroughly cleaned glazed ceramic substrates
Activated sputtering was performed in a mixed gas atmosphere of argon, diborane, and methane by heating the substrate to a temperature of 0.0°C. The total pressure of argon, diborane, and methane is 3.5×10-2To
rr, diborane partial pressure was 1.5×10-4 Ton, methane partial pressure was 1×10-4 Ton, and a film thickness of 1000△ was obtained using a high-frequency two-pole sputtering trowel. The area resistance is 500/mouth (
The specific resistance value was 500 peaks (Q skin). After depositing vanadium at 100A and gold at 1F using an electron beam,
A thermal head pattern with full resolution of 4 lines was formed by selective etching. Next, as a protective film, aluminum oxide (AI2Q) low was laterally layered by sputtering. When this thermal head was subjected to the same acceleration test as in Example 1, the resistance change rate was within ±2%. This example also gave much better results than the thermal head using tantalum nitride in the comparative example. (
Example 9) Tablets were prepared by pressing shelving titanium powder at a washing rate of 100 k9/c or more, and the tablets were placed on a glazed ceramic substrate that had been thoroughly cleaned in advance, with the substrate heated at 300 qo and evacuated to a degree of vacuum of 2 x 10-6 Tom. After that, while introducing methane with a needle valve, the vacuum level was set to 5 x lo-6 Tom.
Then, the prosthesis was performed using an electron beam to a thickness of 1000△.

The area resistance was about 700/mouth (specific resistance value was about 700 μm arc). Next, 10A of titanium and 1.5m of aluminum were deposited on this using an electron beam, and after forming a pattern with a resolution of 4 lines/side by selective etching, 1Am of silicon oxide (Si02) and 1.5m of tantalum oxide were deposited on top of this. (Ta205) was continuously formed into a bran layer by sputtering at loAm to create a thermal head. When this thermal head was subjected to the same acceleration test as in Example 1, good results similar to those of the thermal head were obtained.

When the composition of this film was examined using an ion microanalyzer, it was found that carbon contained 0.02 (atomic ratio) of titanium.

(Example 10) Zirconium shelving (ZrB2) and titanium carbide (TIC)
A homogeneous mixture of powders with a molar ratio of 7:3 was hot-pressed at 1200q0 to form a 5-inch diameter target.

Using this target, thoroughly cleaned glass thickness 5
A 0 mm glazed alumina substrate was heated at 300 qo, and high frequency bipolar sputtering was performed in an atmosphere with an argon pressure of 4 x 10-2 Ton. The sputtering rate was 200A/min, and the input power was 3. When skin/eye sputtering was performed for 5 minutes, a shelved zirconium thin film resistor with a film thickness of 1000 A was obtained. The specific resistance was 1000〆○ arc, and the area resistance was 1000/mouth. On top of this, titanium 10A and aluminum were deposited by lAm electron beam evaporation, a thermal head pattern with a resolution of 4 lines/side was created by selective etching, and on top of this a protective layer of silicon oxide (
1 French m of Si02), 1 m of tantalum oxide (Ta205)
A thermal head was created by continuously laminating a layer of 0 m by sputtering. When this thermal head was subjected to the same acceleration test as in Example 1, good results similar to those of the thermal head were obtained.

(Example 11) Hafnium shelving (Hm2) and zirconium carbide (ZrC
) and a powder mixed uniformly at a molar ratio of 8:2 and pressed at 100k9/ or more to create a tablet.
On a glazed ceramic substrate that has been thoroughly cleaned in advance, the substrate is heated to 300 qo and the vacuum level is 5 x 10-6 Torr.
The thickness of rlooOA was deposited with an electron beam.

The area resistance was about 550/mouth (specific resistance value was about 550 arc). Next, titanium 10△ and aluminum were vapor-deposited using an electron beam of 1.5 mm, and then a pattern with a resolution of 4 lines/side was formed by selective etching, and then silicon oxide (Si02) was deposited 1 mm. A thermal head was fabricated by continuously sputtering 10 m of tantalum oxide (Ta205). When this thermal head was subjected to the same acceleration test as in Example 1,
Good results similar to those obtained with the thermal head were obtained.

Changing the shelving hafnium in this example to another metal shelving,
Similar good results were obtained when zirconium carbide was used in combination with other conductive carbides.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of an example of the shape of a thermal head according to the present invention. FIG. 2 is a characteristic diagram showing the effects of the present invention. DESCRIPTION OF SYMBOLS 1... Substrate, 2... Thin film heating resistor, 3... Electric conductor, 4... Protective layer. East = Figure 2

Claims (1)

[Scope of Claims] 1. A thermal head having a substrate, a heating resistor formed on the substrate, and an electric conductor for supplying power to the heating resistor, in which the heating resistor is made of metal boride and carbon. A thermal head characterized by comprising: 2. The thermal head according to claim 1, wherein the metal boride is zirconium boride. 3. The thermal head according to claim 1, wherein the metal boride is hafnium boride. 4. The thermal head according to claim 1, wherein the metal boride is lanthanum boride. 5 Claim 1 in which the metal boride is titanium boride
Thermal head described in section. 6. The thermal head according to claim 1, wherein the metal boride is tantalum boride. 7 Claim 1 in which the metal boride is niobium boride
Thermal head described in section. 8. The thermal head according to claim 1, wherein the metal boride is tungsten boride. 9. The thermal head according to claim 1, wherein the metal boride is molybdenum boride. 10. The thermal head according to claim 1, wherein the metal boride is chromium boride. 11. The thermal head according to claim 1, wherein the metal boride is vanadium boride. 12 The metal boride is zirconium boride, hafnium boride, lanthanum boride, titanium boride, tantalum boride, niobium boride, tungsten boride, molybdenum boride, chromium boride,
The thermal head according to claim 1, which is a mixture of two or more borides selected from vanadium boride. 13 The carbon content in the heating resistor is 0 of the total amount of metal.
．． 005 (atomic ratio) or more. 14. The thermal head according to claims 1 to 13, wherein the heating resistor is covered with a silicon oxide thin film. 15. The thermal head according to claims 1 to 14, having a tantalum oxide protective film. 16. The thermal head according to claims 1 to 14, which has a protective film of aluminum oxide. 17. The thermal head according to claims 1 to 14, which has a protective film of magnesium oxide. 18. A method for manufacturing a thermal head, characterized in that a heating resistor made of metal boride and carbon is manufactured by sputtering. 19. The method for manufacturing a thermal head according to claim 18, which comprises sputtering in a mixed gas containing argon and methane. 20 The sputtering target is one or two of zirconium boride, hafnium boride, lanthanum boride, titanium boride, tantalum boride, tungsten boride, molybdenum boride, niobium boride, chromium boride, and vanadium boride. Claim 18 or 1 which is a mixture of the above
9. The method for manufacturing a thermal head according to item 9. 21 Zirconium, hafnium, lanthanum, titanium,
The method for manufacturing a thermal head according to claim 18 or 19, wherein one or more metals selected from tantalum, tungsten, molybdenum, niobium, chromium, and vanadium are arranged so as to simultaneously target carbon. . 22. The method of manufacturing a thermal head according to claim 18, wherein sputtering is performed in a mixed gas containing argon, methane, and diborane. 23 Zirconium, hafnium, lanthanum, titanium,
23. The method of manufacturing a thermal head according to claim 18 or 22, wherein the target is one or more metals of tantalum, tungsten, molybdenum, niobium, chromium, and vanadium. 24. The method of manufacturing a thermal head according to claims 18 and 19, wherein the target comprises a mixture of a metal boride and a conductive metal carbide. 25 Metal borides include zirconium boride, hafnium boride, lanthanum boride, titanium boride, tantalum boride, niobium boride, chromium boride, tungsten boride, molybdenum boride,
25. The method of manufacturing a thermal head according to claim 24, comprising one or more types of vanadium boride. 26. Claims characterized in that the conductive metal carbide is made of one or more of zirconium carbide, hafnium carbide, lanthanum carbide, titanium carbide, tantalum carbide, tungsten carbide, molybdenum carbide, niobium carbide, chromium carbide, and vanadium carbide. The method for manufacturing a thermal head according to item 24 or 25. 27 Claim 18, characterized in that sputtering is performed while heating the substrate at 200°C to 500°C.
27. A method for manufacturing a thermal head according to items 26 to 26. 28. A method for manufacturing a thermal head, characterized in that a heating resistor made of metal boride and carbon is manufactured by electron beam evaporation. 29. A method for manufacturing a thermal head according to claim 28, characterized in that electron beam evaporation is performed while introducing a gas containing methane. 30 Tablets include zirconium boride, hafnium boride, lanthanum boride, titanium boride, tantalum boride, niobium boride, chromium boride, tungsten boride, molybdenum boride,
A method for manufacturing a thermal head according to claim 28 or 29, in which the tablet is made of one or more types of vanadium boride. 29. The method for manufacturing a thermal head according to item 29. 32 The metal boride is zirconium boride, hafnium boride, lanthanum boride, titanium boride, tantalum boride, niobium boride, chromium boride, tungsten boride, molybdenum boride,
32. The method of manufacturing a thermal head according to claim 31, comprising one or more types of vanadium boride. 33. Claim 31 or 3, wherein the conductive metal carbide is made of one or more of zirconium carbide, hafnium carbide, lanthanum carbide, titanium carbide, tantalum carbide, tungsten carbide, molybdenum carbide, niobium carbide, chromium carbide, and vanadium carbide. The method for manufacturing a thermal head according to item 32. 34 Claims 28 to 33, in which electron beam evaporation is performed while heating the substrate at 200°C to 500°C
Manufacturing method described in section.