JPS61220301A - Thermal recording head - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermal recording head used in a recording method that performs recording using thermal energy.

[Prior Art] Traditionally, recording methods that use thermal energy have the advantage of being non-impact and therefore producing very little noise during recording, and in recent years have also become capable of color recording. It is gradually attracting attention.

In such a recording method, recorded information is transmitted in the form of an electrical signal to a thermal recording head, that is, an electrothermal conversion element. The electro-thermal conversion element used includes a heat generating resistance layer formed on a base and at least one pair of electrodes connected to the heat generating resistance layer.

Here, the term "substrate" refers to one that supports a heating resistance layer, and the substrate is simply a support with appropriate layers formed thereon, if necessary. Since thermal recording heads are generally relatively small, their heating resistance layers are of a thin film type, a thick film type, or a semiconductor type. especially,
Thin-film types consume less power than other types and have relatively good thermal responsiveness, so they are preferred as components of thermal recording heads, and their applications are gradually increasing.

Therefore, the performance required of the heat generating resistive layer of a thermal recording head is good responsiveness of heat generation to a predetermined electric signal, good thermal conductivity, and good heat resistance against its own heat generation. and that various types of durability (for example, durability against thermal history) are good. Furthermore, when the thermal recording head is used in pressure contact with thermal paper or thermal transfer ink ribbon, it is required that the coefficient of friction with these is small.

However, it cannot be said that the above-mentioned performance is necessarily satisfactory in the heat generating resistive layer of the conventionally used thermal recording head, and further improvement of the characteristics is desired.

Furthermore, in conventional thermal recording heads, a wear-resistant layer is provided on the surface of the heat-generating resistor layer in order to improve wear resistance, but this comes at the expense of thermal responsiveness.

In addition, with conventional thermal recording heads, when recording on a recording medium with a rough surface, such as paper, it is necessary to press the recording medium more firmly in order to record in a perfect dot shape, which reduces the rate of wear. There is a desire for a further improvement in tF.

[Object of the invention] In view of the above-mentioned prior art, one of the four objects of the present invention has been achieved.
One object of the present invention is to provide a thermal recording head having a heat generating resistive layer with improved thermal responsiveness.

Another object of the present invention is to provide a thermal recording head having a heating resistance layer with improved thermal conductivity.

Still another object of the present invention is to provide a thermal recording head having a heating resistance layer with improved heat resistance.

Another object of the present invention is to provide a thermal recording head having a heat generating resistive layer with improved durability.

Another object of the present invention is to provide a thermal recording head having a heating resistance layer with improved wear resistance.

Still another object of the present invention is to provide a thermal recording head having a heat generating resistance layer with a small coefficient of friction.

SUMMARY OF THE INVENTION The above objects are achieved by a novel thermal recording head according to the present invention.

The thermal recording head of the present invention is characterized in that the heating resistance layer is made of an amorphous material having carbon atoms as a matrix and containing silicon atoms, germanium atoms, halogen atoms, and hydrogen atoms.

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 is a partial plan view showing the structure of an embodiment of the thermal recording head of the present invention, and FIG. 2 is a sectional view taken along the line U--■.

In the figure, 2 is a support (substrate here), 4 is a heating resistance layer, and 6 and 7 are a pair of electrodes. 1st
As shown in the figure, a plurality of pairs of a heat generating resistor layer 4 and a pair of electrodes 6.7 connected to the heat generating resistor layer 4 are provided, thereby forming a dot-shaped effective heat generating portion 8.8'. ,8″′
, . . . are arranged on a straight line at predetermined intervals. When the thermal recording head is in use, the heat generating resistive layer 4 side is brought into pressure contact with thermal paper or thermal transfer ink ribbon, etc., and is moved relative to the thermal paper or thermal transfer ink ribbon in the -■ direction. At this time, an electric signal, which is recorded information, is timely applied to the heat generating resistor layer 4 constituting each heat generating part 8.8', 8'', . . . through the electrode 6.7, and based on this, each heat generating part Heat is generated, and the thermal energy at this time is used to perform recording using a thermal method, a thermal transfer method, or the like.

In the present invention, there is no particular restriction on the material of the support 2, but in practice it has good adhesion to the heating resistor layer 4 and the electrodes 6.7 formed on its surface. It is preferable to use a material that has good durability against the heat generated during the formation of the electrodes 6 and 7 and the heat generated by the heat generating resistor layer 4 during use.

The support 2 also has a heating resistance layer 4 formed on its surface.
It is preferable to have an electrical resistance larger than that of the support 2. Furthermore, a material is selected for the support 2 that has thermal conductivity that allows necessary and sufficient thermal energy to be applied to the recording medium side and that does not deteriorate responsiveness to electrical input. .

Examples of the support 2 used in the present invention include those made of inorganic materials such as glass, ceramics, and silicon, and those made of organic materials such as polyamide resin and polyimide resin.

In the present invention, one heating resistance layer 4 is made of an amorphous material having carbon atoms as its base material and containing silicon atoms, germanium atoms, halogen atoms, and hydrogen atoms. Examples of halogen atoms include F, CI, and Br.

I, etc. can be used, and these may be used alone or in combination. As the halogen atom, F and CI are particularly preferable, and F is particularly preferable.

The content of silicon atoms in the heating resistance layer 4 is appropriately selected so as to obtain desired characteristics, but is preferably 0.
．． 0001 to 40 atomic%, more preferably o, o
oos to 20 at%, preferably 0.001-10
In atomic percent.

Ru.

The content rate of germanium atoms in the heating resistance layer 4 is
It is appropriately selected so as to obtain the desired properties, but is preferably 0.0001 to 40 atom%, more preferably 0.0001 to 40 atom%.
．． 0005 to 20 at%, preferably 0.001-
It is 10 atom%.

The content of halogen atoms in the heating resistance layer 4 is appropriately selected so as to obtain desired characteristics, but is preferably 0.
．． 0001 to 30 at%, more preferably 0.0
005 to 20 atomic %, preferably o, ooi-io
It is atomic percent.

The content of hydrogen atoms in the heat generating resistance layer 4 is appropriately selected so as to obtain desired characteristics, and is preferably o, o.
oot to 3o atom%, more preferably 0.000
It is 5 to 20 atomic %, preferably 0.001 to 10 atomic %.

The sum of the silicon atom content, germanium atom content, halogen atom content, and hydrogen atom content in the heat generating resistance layer 4 is appropriately selected so as to obtain desired characteristics, but is preferably 0゜0001 to 40 at%, more preferably 00005 to 30 at%, preferably O, OQ 1 to 20 at%. An amorphous material containing halogen atoms and hydrogen atoms (hereinafter referred to as ra-C:Si:Ge:
It may be abbreviated as (X, H)J. Here, X represents a halogen atom) The heating resistor layer 4 is formed by, for example, a plasma CVD method such as a glow discharge method, or a vacuum deposition method such as a sputtering method.

For example, a-C:Si:Ge:
In order to form the resistance layer 4 made of (X, H), basically the base 2 is placed in a deposition chamber under reduced pressure, and a raw material for C supply that can supply carbon atoms (C) into the deposition chamber is used. A raw material gas for Si supply that can supply gas and silicon atoms (St), a raw material gas for Ge supply that can supply germanium atoms (Ge), and a raw material gas for X supply that can supply halogen atoms (X). A raw material gas for H supply that can supply hydrogen atoms (H) is introduced, and a glow discharge is generated in the deposition chamber using high frequency or microwaves to form a-C on the surface of the substrate 2.
:Si:Ge: A layer consisting of (X, H) may be formed.

In addition, a-C:Si:Ge:
In order to form the resistance layer 4 made of (X, H), basically the substrate 2 is placed in a deposition chamber under reduced pressure, and an inert gas such as Ar, He, etc. or these gases are injected into the deposition chamber. When sputtering a target made of C in an atmosphere of a mixed gas based on C, a source gas for supplying St, a source gas for Ge, a source gas for X, and a source gas for H are present in the deposition chamber. Just introduce gas.

In the above method, the raw material gas for C supply, the raw material gas for Si supply, the raw material gas for Ge supply, the raw material gas for X supply, and the raw material gas for H supply may be in a gas state at normal temperature and pressure. Substances that can be gasified under reduced pressure can be used.

Examples of raw materials for C supply include saturated hydrocarbons having 1 to 5 carbon atoms, ethylene hydrocarbons having 2 to 5 carbon atoms, acetylenic hydrocarbons having 2 to 4 carbon atoms, aromatic hydrocarbons, etc. The saturated hydrocarbons include methane (CH4), ethane (C2Ha), propane (C3Ha), n-butane (n-C4HIO), pentane (C5) (12),
Ethylene hydrocarbons include ethylene (C2H4),
Propylene (C3Ha), butene-1 (C4H8)
, butene-2 (C4H8), inbutylene (C4H
8).

Pentene (C5HIG), acetylene hydrocarbons include acetylene (C2I(2)), methylacetylene (
C3H4), butyne (C4H8), and aromatic hydrocarbons include benzene (CaHe) and the like.

As a raw material for supplying Si, for example, SiH4,5t2
Silicon hydride (H6,5i3) fB, 5i4H16 etc.
silanes), SiF4, (SiF2)5, (S t
F2 ) e, (S i F2 ) 4, Si2 FB
, Si3 FB , SiHF3.5i) I2F2,5
iC14 (SiC12)5. SiBr4, (SiBr2
) 5,5i2C113, 5i2C13F3 and other silicon halides (silane derivatives substituted with halogen atoms).

Examples of raw materials for supplying Ge include GeH4, Ge2
Ha, Ge3Ha, Ge4 HIO.

G C5H12, G 86814. G C7H16,
Germanium hydride such as G e BH18 and GegH2o.

GeF4, (GeF2)5, (GeF2)a, (G
eF2 )4 , Ge2 F6 , Ge3 FB , G
eHF3, GeB2 F2, GeC14 (GeC1
2) s, GeBr4, (GeBr2)s, Ge2
Examples include germanium halides (hydrogen halide derivatives substituted with halogen atoms) such as C1B, Ge2, C13F3, and the like.

Examples of raw materials for supplying X include halogens, halides, interhalogen compounds, halogen-substituted hydrocarbon derivatives, etc. Specifically, the halogens include F2, C12, and Br.
2, I2, halides include HF, HCl,
HBr, HI, BrF, CI as interhalogen compounds
F, ClF3, BrF5, BrF3. HF3,I
F7, IC1, IBr, halogen-substituted hydrocarbon derivatives include CF4, CHF3, CH2F2, CI (
3F, CCl4. CHCl3. CH2CI2. CH3C
l, CBr4, CHBr3, CH2Br2, CH3
Br, CI4, C) LI3, CH2I2.

Examples include CH3I.

Examples of raw materials for supplying H include hydrogen gas and hydrocarbons such as saturated hydrocarbons, ethylene hydrocarbons, acetylene hydrocarbons, and aromatic hydrocarbons, which are also the raw materials for supplying C.

These raw materials may be used alone or in combination.

In the above heating resistance layer forming method, the amount of silicon atoms, the amount of germanium atoms, the amount of halogen atoms, and the amount of hydrogen atoms contained in the resistance layer 4 to be formed and the characteristics of the resistance layer 4 can be controlled. The substrate temperature, supply amount of raw material gas, discharge power, pressure in the deposition chamber, etc. are appropriately set.

The substrate temperature is preferably selected from 20-1500°C, more preferably 30-1200°C, optimally 50-1100°C.

The supply amount of the raw material gas is determined as appropriate depending on the desired performance of the heating resistance layer and the desired film formation rate.

The discharge power is preferably 0.001 to 20 W/crn',
More preferably 0.0l-15W/crn', optimally 0.05-10W/crrfc7).

The pressure inside the deposition chamber is preferably 1O-4 to 1OTorr.
, more preferably 10-2 to 5 Torr.

The resistive layer of the thermal recording head of the present invention obtained using the heat generating resistive layer forming method as described above has properties close to those of diamond. That is, for example, a Vickers hardness of 1800 to 5000.
Thermal conductivity 0.3~2cal/Cmll5eC・℃, resistivity 105~1011Ωfist cm, thermal expansion coefficient 2XlO-5~
10-6/"C1 has a friction coefficient of 0.15 to 0.25 and a density of 1.5 to 3.0, and contains silicon atoms, germanium atoms, halogen atoms, and hydrogen atoms, so it has excellent chemical resistance and Very good flexibility.

In the thermal recording head of the present invention, the resistance layer 4 has particularly good abrasion resistance, so the resistance layer can be made extremely thin, and a special abrasion resistant layer is not required, resulting in extremely good thermal response. you can get something.

However, it goes without saying that a layer having appropriate protection and other functions may be provided on the heat generating resistive layer 4 of the thermal recording head of the present invention. For example, by providing a protective layer, even more durability can be achieved. You can make improvements.

- In the embodiments described above, an example is shown in which the heating resistance layer and the electrodes are provided in this order on the base.

In the thermal recording head of the present invention, the electrode and the heat generating resistive layer may be provided in this order on the substrate. In FIG.
Here, 4 is the heating resistance layer, and 6.7
are paired electrodes.

In this case, since the more durable heat-generating resistive layer is placed on the recording medium side, an extremely excellent thermal recording head can be provided even without providing a wear-resistant layer.

In the above embodiments, the base is simply a support 2.
However, the substrate in the present invention may be a composite. The structure of such an embodiment is shown in FIG. 4, in which the substrate 2 is composed of a support 2a and a surface layer 2b The support material 2a can be made of the support material described in connection with FIG. The surface layer 2b, in which a material with better properties can be used, is made of, for example, an amorphous material having carbon atoms as a host, a conventionally known oxide, or the like. Such a surface layer 2b can be obtained by depositing appropriate raw materials on the support 2a by a method similar to the above-mentioned method for forming the heating resistor layer. Further, the surface layer 2b may be a normal glassy glaze layer.

The electrodes 6.7 in the thermal recording head of the present invention may be of any material as long as they have a predetermined conductivity, such as Au, Cu,
A1. Made of metal such as Ag and Nt.

Next, the outline of the method for manufacturing the thermal recording head of the present invention will be explained.

FIG. 5 is a diagram showing an example of an apparatus used when forming a heating resistance layer on the surface of a substrate. 1101 is a deposition chamber, 1102 to 1106 are gas cylinders, and 1107
~1111 is a mass flow controller, 1112
~1116 are inlet valves, 1117~1121 are outlet valves, 1122~1126 are gas cylinder valves, 1127~1131 are outlet pressure gauges, 1132 is an auxiliary valve, 1133 is a lever, 1134 is a main valve, 1135 is a leak valve, 1136 is a vacuum gauge, 1137 is the base material of the thermal head to be manufactured, 1138
1139 is a heater, 1139 is a base support means, and 11
40 is a high voltage power supply, 1141 is an electrode, 11
42 is a shutter. Note that 1142-1 is a target attached to the electrode 1141 when performing the sputtering method.

For example, 1102 is sealed with CH4 gas (purity of 99.9% or more) diluted with Ar gas, and 1103
SiH4 gas (purity 99.9) diluted with Ar gas
% or more) is sealed, and 1104 contains GeF4 gas (purity of 99.9% or more) diluted with Ar gas.
1105, S i diluted with Ar gas
F4 gas (purity 99.9% or more) is sealed,
1106 contains G e H4 gas (
Purity: 99.9% or higher) is sealed. Before the gas in these cylinders flows into the deposition chamber ttot, the valves 1122 to 112 of each gas cylinder 1102 to 1106
6 and leak valve 1135 are closed, and check that the inflow valves 1112 to 1116, outflow valves 1117 to 1121, and auxiliary valve 1132 are open. First, open the main valve 1134 and start the deposition. When the reading of the zero-order vacuum gauge 1136 for evacuating the chamber 1101 and the gas piping reaches approximately 1.5X10-6 Torr, the auxiliary valve 1132, the inlet valve 1112~
1116 and outflow valves 1117-1121 are closed.

Thereafter, a desired gas is introduced into the deposition chamber 1101 by opening the valve of the gas pipe connected to the cylinder of the gas to be introduced into the deposition chamber 11O1.

Next, an example of the procedure for forming the resistive layer of the thermal recording head of the present invention by the glow discharge method using the apparatus described below will be described. Open the valve 1122 and open the gas cylinder 11.
Let the CH4/Ar gas flow out from 02 and close the valve 1123.
Open the gas pump 1103 to S i H4/A
Let the r gas flow out, open the valve 1124 to let the GeF4/Ar gas flow out from the gas pump 1104, and set the pressure of the outlet pressure gauges 1127, 112B and 1129 to 1 kg/c.
rn' and then inlet valves 1112.1113.
1114e Gradually open mass flow controller 110
7. Let it flow into 1108.1109, then,
Gradually open the outflow valves 1117, 1118, 1119 and the auxiliary valve 1132 to release CH+/Ar gas and SiH4/
Ar gas and G e F 4/Ar gas are deposited in the deposition chamber 110.
Introduced within 1. child .

When , CH4/Ar gas flow rate and S i H4/A
The mass flow controller 1 is adjusted so that the ratio between the flow rate of r gas and the flow rate of G e F 4 / Ar gas becomes a desired value.
107.1108.1109, and also the deposition chamber 11
Adjust the opening degree of the main valve 1134 while checking the reading on the vacuum gauge 1136 so that the pressure inside the main valve 1134 reaches the desired value.

Then, the temperature of the base 1137 supported by the support 1139 in the deposition chamber 1101 is heated by the heater 1138 to a desired temperature, and then the shutter 1142 is heated.
is opened to generate glow discharge within the deposition chamber 1101.

Next, an example of a procedure for forming the resistive layer of the thermal recording head of the present invention by sputtering using one or more devices will be described. On the electrode 1141 to which a high voltage is applied by the high voltage power supply 1140, a high purity graphite
142-1 as a target, CH from the gas pump 1102 in the same way as in the glow discharge method.
4/Ar gas from gas pump 1103 S i H4/
Ar gas and GeF4/Ar gas are introduced into the deposition chamber 1101 from the gas pump 1104 at desired flow rates. By opening the shutter 1142 and turning on the high-voltage power supply 1140, sputtering is performed on the Targetera) 1142-1. At this time, the heater 1138 heats the base 113.
7 to the desired temperature, and the opening degree of the main valve 1134 is set to r! The process of setting the inside of the deposition chamber 1101 to a desired pressure by adjusting the pressure is similar to the case of the glow discharge method.

In the case of a thermal recording head such as that shown in FIGS. 1 and 2, the formation of the heat generating resistive layer on the substrate by one or more of the glow discharge method and sputtering method is carried out over almost the entire surface of the substrate, Thereafter, by forming a conductive layer and etching the conductive layer and heat generating resistive layer using photolithography, a thermal recording head having a plurality of dot-shaped effective heat generating parts as shown in FIG. 1 can be obtained. .

Furthermore, in the case of a thermal recording head as shown in Fig. 3,
After forming a conductive layer on a substrate in advance and etching the conductive layer using photolithography, a heat-generating resistive layer is formed on the substrate by the glow discharge method and snokttering method as described above.

A specific example of the thermal recording head of the present invention will be shown below.

Example 1: Using a substrate made of an alumina ceramic plate with a glaze layer, a heating resistance layer was formed on the surface of the substrate.The heating resistance layer was deposited as shown in FIG. It was carried out by the glow discharge method using the apparatus shown.

CH4/Ar=o, 5 (capacity ratio), Si as raw material gas
H4/Ar=O.

l (capacity ratio) and GeF, c/Ar=0.05 (capacity ratio) were used. The conditions during the deposition were as shown in Table 1.

During the deposition, the opening degree of each valve and other conditions were kept constant, and a heat generating resistor layer having the thickness shown in Table 1 was formed.

After forming an A1 layer on the formed resistance layer by electron beam evaporation, the A1 layer is formed by photolithography.
The layer was etched into the desired shape to form multiple pairs of electrodes.

Subsequently, predetermined portions of the resistive layer were removed by photolithography using an HF-based etching solution. still,
In this example, the size of the resistance layer between the electrode pairs is 200 JLm x 3004 m. A plurality of heat generating resistive elements were fabricated.

The electrical resistance of each heating resistor element of the thus obtained thermal head was measured and found to be 85Ω.

Furthermore, electrical pulse signals were manually applied to each heating resistive element of the thermal head obtained in this example to measure the durability of the heating resistive element.

Note that the duty of the electrical pulse signal is 50%, and the applied voltage is 6.
V, driving frequency 0.5kHz, 1. okHz, 2.0k
Hz.

As a result, in all cases of driving at different driving frequencies, the heating resistor element was not destroyed even when the electrical pulse signal input reached 1XlolO times, and its resistance value hardly changed.

Next, when we printed characters with a composition of 5 horizontal dots x 7 vertical dots using thermal recording paper, we found that 2XlO"
Even after characters are printed, there are still dots and dots on the recorded characters.
There were no problems such as missing parts. Furthermore, it was found that when the thermal head of this example was used as a so-called thermal transfer type in which recording is performed on recording paper via a thermal transfer ink ribbon, it also had extremely excellent durability.

Furthermore, when recording was performed using so-called type paper with a rough surface as recording paper, the thermal head of this example had extremely superior durability performance compared to conventional thermal heads. That is, compared to printing using the conventional thermal head, in which printing defects occurred after 30 million characters, in printing using the thermal head of this embodiment, no printing defects occurred after printing 30 million characters. There wasn't.

Example 2: The raw material gas was CH4/A r=0, 5 (capacity ratio), S
i F4 /Ar=0, 1 (capacity ratio) and GeH
A heating resistor layer having the same thickness was deposited in the same manner as in Example 1 except that 4/Ar=0.05 (capacitance ratio).

Next, when a thermal head was manufactured in the same manner as in Example 1 and an electrical pulse signal was input, the heating resistive element was not destroyed even when the electrical pulse signal input reached 1XloIO times. Further, no change in resistance value was observed.

Next, in the same manner as in Example 1, printing was performed on thermal recording paper, further printing was performed as a thermal transfer type, and further printing was performed on type paper, and as in Example 1, sufficient durability was obtained. It was confirmed that

[Effects of the Invention] According to the present invention, an amorphous material containing carbon atoms as a matrix and containing silicon atoms, germanium atoms, halogen atoms, and hydrogen atoms is used as the heating resistance layer. By being thermo-responsive.

A thermal recording head having extremely good thermal conductivity, heat resistance and/or durability, as well as chemical resistance and flexibility is provided. Further, particularly according to two aspects of the present invention, there is provided a thermal recording head having an excellent heat generating resistance layer having good wear resistance and/or a low coefficient of friction.

[Brief explanation of drawings]

FIG. 1 is a partial plan view of the thermal recording head of the present invention;
The figure is a sectional view taken along line ■-■. 3 and 4 are partial cross-sectional views of the thermal recording head of the present invention. FIG. 5 is a diagram showing an apparatus used for manufacturing the thermal recording head of the present invention. 2 Two substrates 4: Heat generating resistive layer 6.7 Two electrodes 1101: Deposition chamber 1137: Substrate Agent Patent attorney Tsumi Yamashita Figure 1 Figure 2 Figure 4 Figure 3

Claims (8)

[Claims] (1) In a thermal recording head in which at least one set of a heating resistance layer and at least one pair of electrodes electrically connected to the heating resistance layer is formed on a substrate, the heating resistance layer has carbon atoms as a matrix. A thermal recording head characterized in that it is made of an amorphous material containing silicon atoms, germanium atoms, halogen atoms, and hydrogen atoms. (2) The content of silicon atoms in the heating resistance layer is 0.
The thermal recording head of claim 1, wherein the thermal recording head has a content of 0,001 to 40 atom %. (3) The content of germanium atoms in the heating resistance layer is 0.0001 to 40 at%, Claim 1
Thermal recording head. (4) The content of halogen atoms in the heating resistance layer is 0.
The thermal recording head of claim 1, wherein the thermal recording head has a content of 0,001 to 30 at. (5) Hydrogen atom content in the heating resistance layer is 0.00
The thermal recording head of claim 1, wherein the thermal recording head has a content of 0.01 to 30 atom %. (6) The sum of the silicon atom content, germanium atom content, halogen atom content, and hydrogen atom content in the heating resistance layer is 0.0001 to 40 at.%;
A thermal recording head according to claim 1. (7) The thermal recording head according to claim 1, wherein the halogen atom is F or Cl. (8) The thermal recording head according to claim 1, wherein the substrate has a surface layer made of an amorphous material containing carbon atoms as a matrix on the side on which the heat generating resistive layer is formed.