JPH0281401A - Resistor - Google Patents

Abstract

PURPOSE:To obtain higher resistivity as compared with that of a resistor which exhibits metallic behavior and to reduce the temperature dependency of the resistivity by employing a composite material of titanium carbide and silicon carbide as the material of the resistor. CONSTITUTION:In order to form a composite material of titanium carbide and silicon carbide, a vacuum tank 1 is evacuated in vacuum to 10<-3>Torr directly by a conduction heating type CVD device, titanium tetrachloride and silicon tetrachloride are so evaporated with hydrogen gas a carrier gas by bubbling liquids that the pressure in the tank 1 becomes 30Torr to be introduced. An AC current is so supplied to a carbon board 2 that its temperature becomes 1300 deg.C. The formation of a film is conducted for 2 hours to generate a composite film which has 0.2mm of thickness, 20mol% of titanium carbide, 20mol% of silicon carbide on the board 2. The composition of the titanium carbide is ranged at 1-99mol%, and the balance is silicon carbide so that its resistance value can be varied in a wide range.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heating resistor in a thermal head or the like.

rSummary of the Invention] The present invention provides a high-performance heat-generating resistor for use in a thermal head or the like by using a composite material made of titanium carbide and silicon carbide as the resistor material.

[Prior Art] Conventionally, thin film resistors formed by vapor phase plating or printing/sintering have been used as resistors for thermal heads, etc., but these thin film resistor materials include tanker nitride, nichrome, ruthenium oxide, etc. was used.

[Problem to be Solved by the Invention 1] With the recent development of the electronic industry, it is desired to improve the accuracy and stability of heating resistors in thermal heads and the like. However, the resistor materials conventionally used have problems with the resistivity itself, changes in resistivity due to temperature, and reproducibility and reliability. For example, metals such as nichrome and tanker, or interstitial metal compounds such as tantalum nitride and titanium carbide, exhibit gold Or the wiring needed to be thinner and longer. For this reason,
This results in a decrease in yield when manufacturing resistors, and also reduces reliability. Furthermore, in such resistor materials, a large increase in specific resistivity caused by temperature rise due to the application of electric power causes a deviation from the originally intended resistance value.

Additionally, ruthenium oxide, tantalum, and silicon oxide resistors exhibit extremely unstable resistivity due to electrical conduction due to oxygen defects, making them unsuitable for applications that require high reliability. .

[Means for Solving the Problems 1] In order to solve the above problems, a composite material of titanium carbide and silicon carbide is used as a resistor.

[Function] As mentioned above, by using a composite material of titanium carbide and silicon carbide as the resistor material, it has a high specific resistivity compared to primary electrical conduction, and a resistance with a small change in specific resistivity due to temperature changes. It can be a body. Silicon carbide exhibits a specific resistivity that is 10" to 10" times that of titanium carbide near room temperature, and this decreases to 10[deg.] to 10" times that of titanium carbide at high temperatures.

Therefore, at low temperatures, silicon carbide acts like an insulator in titanium carbide, and at high temperatures, it works together with titanium carbide as an electrical conductor, making it possible to obtain higher resistivity than a resistor that behaves like a metal as a whole. At the same time, the temperature dependence of resistivity can be reduced. In this way, by combining titanium carbide, which exhibits metallic electrical conductivity, and silicon carbide, which exhibits semiconducting electrical conductivity, a synergistic effect of both properties appears, resulting in excellent electrical resistance properties even under conditions of large temperature changes. Therefore, it is possible to fabricate a resistor having the following characteristics.

[Example 11] As an example of the present invention, a composite film produced by chemical vapor deposition (CVD) will be described.

FIG. 1 is a longitudinal sectional view of a direct current heating type CVD apparatus for forming a composite material of titanium carbide and silicon carbide according to the present invention.

First, after evacuating the vacuum chamber 1 to 10-' Torr, hydrogen was added so that the pressure inside the vacuum chamber 1 became 30 Torr.
Propane, titanium tetrachloride, and silicon tetrachloride were introduced. At this time, titanium tetrachloride and silicon tetrachloride were vaporized by bubbling using hydrogen gas as a carrier gas, and introduced into the vacuum chamber 1. Each gas flow rate was as follows. In addition, the carbon substrate 2, which is a substrate, has
An alternating current was applied so that the temperature reached 1300°C.

(Gas flow conditions) Hydrogen...700 cc/min Propane...50 cc/min Titanium tetrachloride...l Occ/min Silicon tetrachloride
... After 2 hours of film formation at 30 cc/min, titanium carbide 20 was deposited on carbon substrate 2 with a film thickness of 0.2 mm.
A composite film having a composition of 1% mole and 80 mo1% silicon carbide was produced.

Figure 2 shows the results of making the product into a plate shape by scraping off the carbon and measuring the change in specific resistivity with respect to temperature.
0 times, the change in he resistivity with respect to temperature is also extremely small,
It was found that it is optimal as a heating resistor for thermal heads, etc.

[Example 2] As an example of the present invention, a composite film of titanium carbide and silicon carbide produced by reactive ion plating will be described.

FIG. 3 is a longitudinal cross-sectional view of a reactive ion blasting apparatus for forming a composite film of titanium carbide and silicon carbide according to the present invention.

First, after evacuating the vacuum chamber 3 to 10-' Torr, acetylene (C, H2) partial pressure is 3 x 1 O Torr, tetramethylsilane (Si(C)(,)4) partial pressure is 1 x lO-
Titanium 4 was heated and evaporated by an electron beam evaporator 5 in a Torr atmosphere, and a discharge plasma was formed by applying power of +50 V and 50 A to the ionization electrode 6 placed above the titanium 4. After stabilization, the shutter 7 was opened and reactive ion blating was performed for 5 minutes, and a composite film of 5,000 titanium carbide and silicon carbide was formed on the alumina substrate 8.

When the relationship between temperature and specific resistivity of this sample was examined, it showed the same tendency as Example 1, and it was confirmed that it could be used as a precision heating resistor in a thermal head or the like.

[Example 3] Next, the present invention will be described with reference to an example using a reactive high frequency sputtering method as a manufacturing method.

First, the vacuum chamber was evacuated to 1X10-'Torr, then argon gas was introduced to 5X10-'Torr, and the surface of the metal titanium target was sufficiently pre-sputtered to clean the target surface. Furthermore, the glass substrate was cleaned by reverse sputtering.

Next, the partial pressure of argon is set to 1
IO-”Torr, the partial pressure of methane (CH,) is lXl0
Each gas was introduced to the target so as to maintain the discharge. At this time, 300 W of high frequency power was applied to the target to maintain the discharge. After stabilization, the shutter was opened and the glass substrate was placed on the glass substrate. A composite film of 2,000 titanium carbide and silicon carbide was formed.

Similar to Example-1, the material produced by this method also showed a high specific resistance value and low temperature dependence of the specific resistance.

[Effects of the Invention] According to the present invention, it is possible to utilize both the metallic electrical conductivity of titanium carbide and the semiconducting electrical conductivity of silicon carbide. It became possible to reduce the dependence of specific resistivity on As a result, it can be applied as an extremely reliable and stable resistor material to fine heating resistors such as thermal heads. In other words, by increasing the specific resistivity, it is possible to increase the thickness of the thin film resistor, which is the heat generating part, and eliminate the need to intentionally reduce the wiring width, thereby increasing reliability. In terms of mass production, it is possible to significantly improve yields in photolithography processes, etc. compared to conventional methods.Furthermore, since the temperature dependence of specific resistivity is small, high-speed temperature control is possible. .

In addition, in the example, the compositions of titanium carbide and silicon carbide were 20 mo1% and 80 mo1%, respectively, but by setting the composition of titanium carbide in the range of 1 to 99 mo1% and the remainder being silicon carbide, the resistance value can be varied over a wide range. Experiments have shown that it is possible to change the

In addition, in the examples, the PVD method, the reactive ion blating method, and the reactive sputtering method were mentioned as the manufacturing method of the composite material resistor of titanium carbide and silicon carbide of the present invention, but other methods, such as the sputtering method In this process, the composite material of titanium carbide and silicon carbide according to the present invention is used as a target material to form a resistor, or the plasma CVD method is used, or the powder of this material itself is made into a paste form, printed and fired to form a resistor. There are various methods that can be considered, but it goes without saying that the same effects as the methods described in the examples can be expected with either method.

[Brief explanation of the drawing]

FIG. 1 was shown in Example-1. 1 is a longitudinal cross-sectional view of a CVD apparatus which is a method for manufacturing a resistor according to the present invention. Second
The figure is an explanatory diagram showing the relationship between temperature and specific resistivity of the resistor manufactured in Example-1. Moreover, FIG. 3 shows the example-
FIG. 2 is a longitudinal cross-sectional view of an ion blating device for the reactive ion blating method, which is a specific method for manufacturing a resistor according to the present invention as described in Section 2; l...Vacuum chamber, carbon substrate, vacuum chamber, titanium, electron beam evaporator, ionization electrode, shutter, substrate

Claims (3)

[Claims] (1) A resistor characterized in that a composite material of titanium carbide and silicon carbide is used as a resistor material in a heat generating resistor used for a thermal head or the like. (2) Claim 1, characterized in that the content of titanium carbide in the resistor material is 1 to 99% in molar ratio, and the remainder is silicon carbide.
Resistor described in section. (3) The resistor according to claim 1, wherein a composite material of titanium carbide and silicon carbide is produced by a chemical vapor deposition method or a physical vapor deposition method.