JP3208290B2 - Method of forming thin film member - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a thin film member which can be easily formed by applying a thin film member such as a thin film resistor and a thin film circuit on a substrate.

[0002]

2. Description of the Related Art Conventional thin film members such as a thin film resistor and a thin film circuit formed on a recording head of a semiconductor integrated circuit or a thermal printer are formed by sputtering or PCVD. Of the resistor or the electrode was formed.

[0003]

However, in such a conventional method for forming a thin film member, since the vacuum film forming apparatus is expensive, the initial investment becomes enormous, and there is no great risk for commercialization. And the final product was expensive. Also, in terms of production efficiency, there is a problem that a considerable amount of time is required until the product is completed because the film forming speed is slow and the number of processes is large.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has been made in consideration of the above problems, and has a thin film resistor and a thin film resistor having the same function as a thin film circuit and a thin film circuit formed by sputtering or PCVD. It is an object of the present invention to provide a method of forming a thin film member that can easily and inexpensively form the above circuit.

[0005]

According to a first aspect of the present invention, there is provided a method of forming a thin film member, comprising: [Wherein R 1 and R 2 are hydrogen, an alkyl group having 1 to 6 carbon atoms,
Alkene, alkyne, cycloalkyl and aryl groups. Further, m and n are molar ratios indicating the ratio of the number of each monomer to the total monomers in the polymer. Heating the substrate coated with the silicon-based copolymer having the structure of the above in an inert atmosphere, and thermally decomposing the silicon-based copolymer so as to have conductivity to form a thin-film resistor on the substrate. Features.

[0006] The method for forming a thin film member according to claim 2 is characterized in that:

[Chemical formula 2] [Wherein R1 and R2 are hydrogen, an alkyl group having 1 to 6 carbon atoms, an alkene group, an alkyne group, a cycloalkyl group, and an aryl group. Also, l, m, and n are molar ratios indicating the ratio of the number of each monomer to the total monomers in the polymer. The substrate coated with the silicon-based copolymer having the structure described above is irradiated with electromagnetic waves through a mask pattern to form a desired resistor pattern shape, and then heated in an inert atmosphere to make the silicon-based copolymer conductive. And forming a thin film resistor on the substrate by thermal decomposition.

Further, a method of forming a thin film member according to claim 3 is

[Chemical formula 2] [Wherein R1 and R2 are hydrogen, an alkyl group having 1 to 6 carbon atoms, an alkene group, an alkyne group, a cycloalkyl group, and an aryl group. Also, l, m, and n are molar ratios indicating the ratio of the number of each monomer to the total monomers in the polymer. The substrate coated with the silicon-based copolymer having the structure of [1] is heated in an inert atmosphere to thermally cure the silicon-based copolymer, and then irradiated with a laser through a mask pattern in the inert atmosphere to obtain a desired conductivity. A thin film circuit is formed on a substrate by forming a resistor pattern and a conductor pattern having the following.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below.

The present inventors have conducted intensive studies to improve the method of forming a thin film member such as a thin film resistor and a thin film circuit. As a result, the silicon-based copolymer was irradiated with energy after heating or by laser or the like. It was found that it remained almost even afterwards and had conductivity depending on the heating temperature or irradiation energy amount, and succeeded in applying this to a method for forming a thin film member.

That is, when a silicon-based copolymer containing silicon as a skeleton is compared with a polymer having a skeleton formed only with carbon, a polymer having a skeleton formed only with carbon after firing in an inert atmosphere is used. Is almost thermally decomposed and vaporized, whereas the silicon-based copolymer remains as a composite of SiC and C. In particular, in the case of a silicon-based copolymer of a type in which the molecules are cross-linked, when the density is high, most of the silicon-based copolymer remains even after firing to form a dense thin film. The silicon-based copolymer having this property is represented by the following chemical formulas 1 and 2
Is a silicon-based copolymer having the structure described in (1).

[Chemical formula 1] [Wherein R 1 and R 2 are hydrogen, an alkyl group having 1 to 6 carbon atoms,
Alkene, alkyne, cycloalkyl and aryl groups. Further, m and n are molar ratios indicating the ratio of the number of each monomer to the total monomers in the polymer. ]

[Chemical formula 2] [Wherein R1 and R2 are hydrogen, an alkyl group having 1 to 6 carbon atoms, an alkene group, an alkyne group, a cycloalkyl group, and an aryl group. Also, l, m, and n are molar ratios indicating the ratio of the number of each monomer to the total monomers in the polymer. This is represented by H of Formula 1 and C of Formula 2
The free radicals are cross-linked by cleavage at the triple bond portion, that is, the bonding portion is separated and the other free radicals are bonded to each other to improve heat resistance.

Next, the respective states of the silicon-based copolymer with respect to the firing temperature will be described.

First, when the silicon-based copolymer is heated to 300 ° C. to 400 ° C. in an inert atmosphere, the color changes from yellow translucent to brown and is completely thermoset. At this time, the silicon-based copolymer is an insulator. When a laser having an energy of 50 mJ or more is irradiated from this state in an inert atmosphere, the irradiated portion becomes conductive. The wavelength of the laser to be irradiated does not need to be limited, since the silicon-based copolymer becomes brown after thermal curing and easily absorbs the laser, but it is not particularly limited.
There is an AG laser or the like.

Further, the silicon-based copolymer is heated at 500 ° C.
When heating in an inert atmosphere as described above, desorption of H and the like occurs due to thermal decomposition, and mineralization proceeds. But,
When the silicon-based copolymer is heated in an inert atmosphere at a temperature of 1000 ° C. or more, crystallization progresses gradually, and when the heating temperature is increased to about 1300 ° C. and baked, the silicon-based copolymer is subjected to X-ray diffraction measurement. , The diffraction peak of β-SiC is clearly confirmed. The silicon-based copolymer thus formed is
A state in which the iC crystal and carbon are mixed in a nano-order unit becomes a high-performance conductive ceramic having high heat resistance, high hardness and high toughness.

However, the silicon-based copolymer is
The method of forming a thin film by heating at a temperature of not less than ° C. requires a large amount of power energy at the time of firing, and the material such as electrodes and substrates is limited to those having heat resistance.

Therefore, in each example of the embodiment of the present invention, a method of forming a resistor and a circuit in a range in which the firing temperature is 300 ° C. to 800 ° C. and which is industrially effective will be described.

Next, the mechanism of generating conductivity obtained by firing the above-mentioned silicon-based copolymer will be described.

The silicon-based copolymer is an electrical insulator before firing or before laser irradiation. However, when the silicon-based copolymer is fired or laser-irradiated in an inert gas such as Ar or the like, the cyclization of C in the silicon-based copolymer proceeds, and the silicon-based copolymer is converted into carbon black in accordance with the firing temperature. become. In particular, a silicon-based copolymer having a large proportion of double bonds after firing, such as a bond represented by R1 and R2 in Chemical Formula 1 and a triple bond in C in Chemical Formula 2, is thermally decomposed by firing at a low temperature of 800 ° C. or lower. At the time of disassembly by irradiation of energy such as laser
It has a structure similar to thermally stable carbon black and has conductivity.

Conversely, the silicon-based copolymer is When the ratio of the structure is large, the firing temperature is set to 800
When baked below ℃, conductivity is low, but oxidation resistance,
A thin film having excellent wear resistance can be obtained.

Therefore, by irradiating a laser beam through the mask pattern, an insulator pattern and a conductor pattern having a line width of 1 μm or less can be easily formed, and the irradiation energy can be changed by changing the irradiation energy. A resistor pattern and a conductor pattern according to the amount of energy can be easily formed.

[0020]

Next, an embodiment of a method of forming a thin film member for forming a thin film resistor according to the present invention will be described.

In the method of forming a thin film member according to this embodiment, a silicon-based copolymer having the structure of the following chemical formula 1A is dissolved in a solvent such as toluene, coated uniformly on a quartz substrate or the like by spin coating, and then dried. Then, firing is performed in an inert atmosphere. The firing conditions are as follows: firing time is 1 hour, firing temperature is 500 hours.
C. and 800.degree. C. When the firing temperature is 500 ° C., the resistance value is 0.5 (Ω · Cm),
When the firing temperature is 800 ° C., the resistance is 0.05 (Ω · C
m).

In addition, structures having the same effects as those of the chemical formula 1A include structures represented by the following chemical formulas 1B and 1C. Etc.

Next, a description will be given of a second embodiment of the method for forming a resistor according to the present invention.

The method of forming a resistor according to the second embodiment is as follows. A silicon-based copolymer having a triple bond of C as shown in the following chemical formula 2A is dissolved in a solvent such as toluene, and the quartz substrate is uniformly coated by spin coating or the like. And dried, and then irradiated with ultraviolet rays through a mask pattern. The portion irradiated with the ultraviolet rays has a property that C forms a network and is hardly soluble in a solvent. For this reason, after removing the unexposed portion masked with a solvent such as toluene, a 1 μm resistor pattern shape is formed by the exposed portion and the unexposed portion, and the resistor is formed by firing this. Is done. In addition, the structure that can obtain the same effect as in Chemical Formula 2A includes:
As shown by the following Chemical Formula 2B, Chemical Formula 2C and Chemical Formula 2D, Etc.

Next, an example of the embodiment of the method of forming a thin film member for forming a thin film circuit in the present invention will be described.

As an example, a method of forming a circuit of a thermal head as shown in FIGS. 1 and 2 will be described. In this example, a glaze layer 2 laminated on an alumina substrate 1 was prepared by dissolving a silicon-based copolymer having a triple bond of C as shown in the following chemical formula 2A in a solvent such as toluene.
It is applied on top and heated from 300 ° C. to 400 ° C. to be thermally cured. When cured as described above, the film is not scattered even when the laser is irradiated, and the laser is easily absorbed. After the curing, the silicon-based copolymer is covered with a resistor mask, and a laser is irradiated with a YAG laser or the like to form a resistor pattern, thereby forming a heating element 3. Next, a conductor pattern is formed by irradiating a laser on the silicon-based copolymer covered with an electrode portion mask to form a common electrode 4 and individual electrodes 5. This conductor pattern and the resistor pattern,
It is formed into a thin film having a thickness of 2 to 5 μm. afterwards,
Silicon oxide, glass, or the like is applied on these patterns and fired at a firing temperature of 500 ° C. or less to form an overcoat layer 6 having a thickness of about 5 μm having oxidation resistance and wear resistance.
To form a thermal head. In addition, since the conductivity (resistance value) of the silicon-based copolymer changes depending on the irradiation energy of the laser, the laser irradiation time for forming the above-described resistor pattern and the conductor pattern is set to a desired resistance value. Time. Table 1 below shows the relationship between the irradiation energy and the resistance value. Becomes

In addition, structures having the same effects as those of the chemical formula 2A include the following chemical formulas 2B, 2C, and 2C.
D and as shown by Formula 2E: Etc.

In each of the embodiments and examples of the present invention described above, the property that the silicon-based copolymer becomes conductive by heat or irradiation energy is used for sputtering or PCVD. A thin film member such as a thin film resistor and a thin film circuit having the same function as the formed thin film resistor and thin film circuit can be formed easily and inexpensively by coating.

The present invention is not limited to the above-described embodiment, but can be variously modified as needed.

For example, in the method of forming a thin film resistor, an example of an electromagnetic wave to be applied is to irradiate an ultraviolet ray to impart conductivity to the silicon-based polymer. However, the present invention is not limited to this ultraviolet ray. Any other electromagnetic waves such as X-rays and X-rays may be used as long as they can form a resistance pair pattern.

[0031]

As described above, the method for forming a thin film member according to the present invention utilizes the property that a silicon-based copolymer becomes conductive by heat or irradiation energy.
The thin film resistor and the thin film member having the same function as the thin film circuit formed by sputtering or PCVD can be easily and inexpensively formed by coating.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a thermal head for explaining one embodiment of a method of forming a thin film member according to the present invention.

FIG. 2 is a side sectional view of FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 alumina substrate 2 glaze layer 3 heating element 4 common electrode 5 individual electrode 6 overcoat layer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI B05D 7/00 B05D 7/00 H 7/24 302 7/24 302Y B41J 2/335 H01L 21/208 Z H01L 21/208 29 / 28 51/00 B41J 3/20 111H (56) Reference JP-A-58-219792 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01C 17/00-17/30

Claims (3)

(57) [Claims] [Chemical formula 1] [Wherein R 1 and R 2 are hydrogen, an alkyl group having 1 to 6 carbon atoms,
Alkene, alkyne, cycloalkyl and aryl groups. Further, m and n are molar ratios indicating the ratio of the number of each monomer to the total monomers in the polymer. A substrate coated with the silicon-based copolymer having the structure of the above, is heated in an inert atmosphere, and the silicon-based copolymer is thermally decomposed to form a thin-film resistor on the substrate. Forming method. [Chemical Formula 2] [Wherein R1 and R2 are hydrogen, an alkyl group having 1 to 6 carbon atoms, an alkene group, an alkyne group, a cycloalkyl group, and an aryl group. Also, l, m, and n are molar ratios indicating the ratio of the number of each monomer to the total monomers in the polymer. The substrate coated with the silicon-based copolymer having the structure described above is irradiated with electromagnetic waves through a mask pattern to form a desired resistor pattern shape, and then heated in an inert atmosphere to thermally decompose the silicon-based copolymer. Forming a thin-film resistor on the substrate by performing the method. [Chemical Formula 2] [Wherein R1 and R2 are hydrogen, an alkyl group having 1 to 6 carbon atoms, an alkene group, an alkyne group, a cycloalkyl group, and an aryl group. Also, l, m, and n are molar ratios indicating the ratio of the number of each monomer to the total monomers in the polymer. The substrate coated with the silicon-based copolymer having the structure of the above is heated in an inert atmosphere, and the silicon-based copolymer is thermally cured, and then irradiated with a laser through a mask pattern in an inert atmosphere to form a resistor pattern and A method for forming a thin film member, comprising forming a conductive pattern to form a thin film circuit on the substrate.