JP3391967B2 - Substrate for inkjet recording head, inkjet recording head, and inkjet recording apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention utilizes thermal energy to eject a liquid, for example, an ink, preferably to fly it to form a desired image on a medium such as plain paper, processed paper, cloth or OHP paper. an ink jet recording head and an ink jet recording apparatus for further relates heat generating member for Lee inkjet recording head (substrate), in particular, heating resistors and realization of high density multi-level ink jet recording head having a plurality of heating elements in the nozzle The present invention relates to a head capable of achieving durability and stabilization of a heat generation state by including a crystal structure of TaN _0.8 . INDUSTRIAL APPLICABILITY The inkjet recording head of the present invention can be applied to a device having various output functions such as a printer, a facsimile, a copying machine, or a multi-function peripheral, and a system for printing desired recording on a desired medium using the device.

[0002]

2. Description of the Related Art Ink is ejected using heat energy,
It has been confirmed that the inkjet method is effective as a recording apparatus for forming a desired image on a medium such as plain paper, processed paper, cloth, or OHP paper, which is preferably caused to fly. Among them, the bubble jet method is capable of causing film boiling to ink and ejecting ink droplets to achieve stable on-demand recording. A basic patent thereof is US Pat. No. 4,849,774. There is one described in the specification (West German Registration No. 2843064 specification).

In this patent, as an example of a heating resistor for ejecting ink, tantalum nitride, HfB ₂
Etc. are listed. At the stage of completion of these basic patents, these heat generating resistors satisfied the printing speed and printing conditions at the level of those days (before 1977). However, it is not tantalum nitride that has been put into practical use that satisfies the recent market requirements (currently since 1983) such as stability and durability for a large number of discharge ports such as 10 to 64, but HfB ₂ or TaAl. Is limited to. That is, the tantalum nitride recognized in the above publication is a TaN resistor single body, a Ta ₂ N resistor single body or a mixed resistance thereof as described in US Pat. No. 3,242,006. It was just a body.

Using tantalum nitride as a heating resistor,
There are many known documents regarding thermal heads that come into direct contact with thermal paper or ink ribbon. However, this heating resistor is equivalent to the resistor disclosed in the above-mentioned US Pat. No. 3,242,006. Of particular interest is the Ta ₂ N heating resistor oriented in the (101) direction described in US Pat. No. 4,737,709. The US patent invention is focused on orientation among Ta ₂ N heating resistors, employing a Ta ₂ N heating resistors aligned in the (101) direction as being capable of improving the durability.

It should be noted here that the TaN heating resistor, which is mainly used in the thermal head, is not used in the ink jet recording head. Considering this reality, the following reasons can be given. That is, in the thermal head, the electric power applied to the heating resistor is about 1 W in 1 msec, whereas in the ink jet recording head, in order to vaporize the ink in a short time, for example, 3 W or more in 7 μsec. Power of 4 W or less is applied to the heating resistor. This is several times as large as the electric power applied to the heating resistor of the thermal head. Therefore, when the conventional tantalum nitride (TaN resistor alone, Ta ₂ N resistor alone or a resistor in which these are mixed) is used as a heating resistor of the ink jet recording head and driven, the heating resistor applies power. Therefore, the resistance value tends to increase in a short period of time. This change in resistance value can be seen in the thermal head to some extent, but does not cause a rapid deterioration of the image. On the other hand, in the ink jet recording head, the generation of bubbles is made unstable so that the amount of ink droplets itself is reduced, and as a result, the recording quality is degraded. Similarly, it was found that the Ta ₂ N resistor had a resistance value remarkably decreased by the same application of electric power, and the wire was initially broken, so that it could not be put to practical use as a head.

From the above points, the TaN heating resistor in the field of the conventionally known thermal head has not been practically used in the recent ink jet head,
At its practical level, HfB ₂ is mainly used.

Under such circumstances, as for the ink jet recording head, a multi-value output color ink jet head having a plurality of heating elements in the nozzle was devised as described in Japanese Patent Publication No. 62-48585. There is.
For example, two heating elements are provided in the nozzle and are individually connected to drive drivers so that they can be independently driven, and the element sizes are made different, for example, 1: 2. At this time, if the print dot by the small heater is set to 1, the print dot by the large heater is set to 2, and if both heaters are driven simultaneously, the print dot is set to 4. By utilizing the fact, the gradation value of 4 values with 1 nozzle is obtained. Is what you are trying to get. This element structure is hereinafter referred to as a double heater.

[0008]

HfB ₂ is, in comparison with tantalum nitride (TaN alone, Ta ₂ N _hex alone),
Although it has been evaluated and used as a material for a heating resistor of an ink jet recording head, it is difficult to stably obtain a level enough to satisfy further market demands. By, in particular,
It has been found that the multi-valued inkjet recording head has an inconvenient problem.

That is, the HfB ₂ film is usually produced by the RF sputtering method, but HfB ₂ contains 1 impurity.
%, The probability of defects occurring in the resistor is high,
Further, in the double heater, which has a large variation in durability of the heater, in order to obtain the same print density, the heating element of the conventional head must be driven twice while being driven once. Moreover, since the double heaters are adjacent to each other with a gap of several μm, they are greatly affected by the heat generation of each other, and as a result, the thermal stress on the heating element becomes extremely large,
It has been found that fB ₂ has a durability no more than half that of the conventional device.

Further, in the case of the double heater, the heater needs a drive transistor of 1: 1 and the element density of double the nozzle density is required for the transistor. For example 36
If it is 0 DPI, it is 35 μm, and if it is 900 DPI, it is 15 μm. A conventional heating element is generally a bipolar transistor, and the element density in the nozzle direction is at most 70 μm. It has been found that in order to increase the element density further, it is necessary to devise a transistor in two stages, and in such a case, the wiring becomes complicated and the shape of the head substrate becomes large. .

In view of the above, a main object of the present invention is to provide an ink jet recording head and an ink jet recording apparatus which solve the above-mentioned problems with a double heater for a multi-value ink jet recording head and have high density and excellent durability. It is in.

[0012]

The above objects of the present invention are as follows.
An ink jet recording head in which a double heater having two heating resistors is provided in the nozzle, and the thermal energy from the heating resistors is used to eject ink from an ejection port to perform recording on a recording medium. In front
Heating resistor of the serial double heater is only contains the crystal structure of the TaN _0.8, and the two heating resistors next door with a gap of a few μm
This can be achieved by an inkjet recording head characterized by being in contact with each other .

Further, according to the present invention, there is provided an ink jet recording head substrate comprising the double heater , the ink jet recording head according to the present invention wherein the driving transistor of the heating element is an N-MOS transistor, and a recording medium. It also includes an inkjet recording apparatus comprising at least the inkjet recording head of the present invention having an ejection port for ejecting ink to a recording surface and a member for mounting the head. To do.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below.

FIG. 1 is a schematic sectional view showing a sectional structure of a portion corresponding to an ink path of a substrate 100 for an ink jet recording head of the present invention. In FIG. 1, 101 is a silicon substrate, and 102 is a thermal oxide film which is a heat storage layer. 1
Reference numeral 03 is an SiO film or SiN film which is an interlayer film also serving as a heat storage layer, 104 is a resistance layer, and 105 is Al or A.
Al alloy wiring such as l-Si and Al-Cu, and 106 are SiO films, SiN films or SiO films which are protective films. Reference numeral 107 is a cavitation resistant film for protecting the protective film 106 from chemical and physical shocks due to heat generation of the resistance layer 104. Reference numeral 108 denotes a heat acting portion of the resistance layer 104 in a region where the electrode wiring 105 is not formed.

The resistance layer 104 serves as a heat generating resistor as a functional element.
A layer for positioning the antibody between the wires 105 as electrodes
It The present invention relates to a heat generating resistor which is constituted by the resistance layer 104.
Body is TaN_0.8 Is characterized by including the crystal structure of
It This is, for example, TaN_{0. 8} And Ta₂ Including N,
More preferably that TaN_0.8 Is 17 mol% or more 10
Less than 0 mol% or TaN_0.8 And Ta
N, and more preferably its TaN_0.8 Is 20 mol
% Or more and less than 100 mol%. As a manufacturing method, for example
For example, tantalum (Ta) material (purity 99.99%)
Used for getting, argon gas (Ar) and nitrogen gas
(N₂ ) Is used as the sputtering gas and N ₂ Partial pressure, atmosphere
Control the ambient temperature and substrate temperature within the specified range.
The tantalum tar by the reactive sputtering method
Sputtering the get with the sputtering gas
Than TaN_0.8 A fine polycrystalline film with
It This TaN_0.8 Film with a double heater for heat generation
If used as a resistor, the heating resistor will be used continuously for a long period of time.
Even if there is, there is very little change in resistance value, long life and reliable
It will be highly responsive. In the example of FIG. 1, there is no heating resistor part.
By the way, the entire resistance layer 104 is TaN._0.8 Including the configuration
Has become. This TaN_0.8 Heating resistors including
There is little variation in the above, and many on the same substrate (or base)
Even if several heating resistors are formed, the stability of the functional effect can be obtained.
Be done. In addition, resistance changes even when energized under various conditions.
The number of heat generating resistors is stable and the functions are the same.
Can exert the action of.

FIG. 2 is a top view of a main portion of one nozzle of a substrate for an ink jet recording head in which a double heater is applied to which the substrate structure of FIG. 1 is applied. The double heater has the configuration of FIG. 1 as the heating resistor 201,
A segment of 201, 202 and 2 elements is for one nozzle. The space between the two elements of the double heater is several μm. 201 and 202 are drive drivers 2 separately
It is connected to 03 and 204. 203 is a power supply line.

FIG. 3 is an equivalent circuit of the ink jet recording head substrate. In FIG. 3, in addition to the double heater (heating resistors 201 and 202) configured in one nozzle and the N-MOS transistor 301 which is a drive transistor, CM
A shift register 302 composed of an OS transistor for processing a drive signal, a latch 303 for holding data,
Block selection signal 30 for dividing the nozzle into blocks
AND the 4 and those data with the drive pulse signal 305
306 and the like. Further, a temperature adjustment sub-heater 307, a temperature sensor 308, a heater resistance value monitor heater 309, and the like are configured. These driving elements are formed on a Si substrate by semiconductor technology, and the heat acting portion is further formed on the same substrate.

FIG. 4 shows a schematic cross-sectional view of the main element of the substrate cut longitudinally. Si substrate 4 of P conductor
01, a P-MOS 450 is formed in the N-type well region 402 and an N-MOS 451 is formed in the P-type well region 403 by introducing and diffusing impurities such as ion plantation using a general MOS process. The P-MOS 450 and the N-MOS 451 are formed to have a thickness of 4000 angstroms or more and 5000 angstroms or less through a gate insulating film 408 having a thickness of several hundred angstroms.
Gate wiring 415 made of poly-Si deposited by the method and the source region 40 introduced with N-type or P-type impurities
5, drain region 406, etc., and these P-MO
A C-MOS logic is composed of S and N-MOS. The element driving N-MOS transistor is also composed of the drain region 411, the source region 412, the gate wiring 413, etc. in the P-well substrate by the steps of impurity introduction and diffusion.

Here, the element driving driver includes an N-MOS.
When a transistor is used, the distance L between the drain gates forming one transistor is about 10 μm at the minimum value, and a double heater can achieve a density of 900 DPI or more. The breakdown of 10 μm is that the source / drain conduct 417 is 2 × 2 μm, but since half of it is also used as an adjacent transistor, it is half that, which is 2 μm, and between the conduct 417 and the gate 413 is 2 × 2 μm. 4 μm, the gate 413 is 4 μm, and the total is 10 μm. In addition, an oxide film isolation region 453 is formed between the respective elements by field oxidation with a thickness of 5000 angstroms or more and 10000 angstroms or less to isolate the elements. This field oxide film acts as a first-layer heat storage layer 414 under the heat acting portion 108.

After each element is formed, the interlayer insulating film 416 is formed.
Is deposited to a thickness of about 7,000 angstroms by PSG, BPSG, etc. by the CVD method, is planarized by heat treatment, and then through the contact hole, the first layer of Al
Wiring is performed by electrodes 417 (conduct).
Then, an interlayer insulating film 418 of SiO or the like is deposited by plasma CVD to a thickness of 10000 angstroms or more and 15000 angstroms or less, and TaN of the present invention having a thickness of about 1000 angstroms is formed as a resistance layer 104 through a through hole. _{A 0.8 hex} film is formed by the DC sputtering method. After that, a second-layer Al electrode which will be a wiring to each heating element is formed. Next, as the protective film 106, a SiN film formed by plasma CVD is used for about 1000
The film is formed to a thickness of 0 angstrom. A cavitation resistant film 107 is deposited on the uppermost layer of Ta or the like to a thickness of about 2000 angstroms.

After the recording head substrate is completed, as shown in FIG. 5, ejection ports for ejecting ink are formed to form an ink jet recording head. In FIG. 5, 100 is a substrate, 1
10 is a heat generating part, 500 is a discharge port, 501 is a liquid path wall member,
Reference numeral 502 is a top plate, 503 is an ink supply port, 504 is a common liquid chamber, 505 is a liquid passage, 506 is wiring, and 510 is a recording head. FIG. 6 is a schematic diagram of driving of a heating element of an inkjet head, foaming, and ejection of ink droplets. 6 in FIG.
01 is an ink discharge liquid, 602 is a bubble, 603 is ink,
Reference numeral 604 is a driving unit, 605 is a shift register, and 207 is an ink ejection port.

As the recording liquid (ink) applicable to the ink jet recording head of the present invention, various liquids can be used, but generally, the dye is 0.5 wt% to 20%.
Those having an ink composition of 10% by weight to 90% by weight of a water-soluble organic solvent such as (wt%) (polyhydric) alcohol or polyalkylene glycol can be preferably used. As an example of the specific ink composition, C.I. I. 3% by weight of Food Black 2 and 25% by weight of diethylene glycol,
20 wt% N-methyl-2-pyrrolidone, 52 w water
An example of the structure is t%.

Next, an ink jet recording apparatus using the recording head of the present invention will be described with reference to FIG. FIG. 7 shows an inkjet recording apparatus 210 to which the present invention is applied.
It is a general | schematic perspective view which shows an example of 0.

The recording head 2200 has a drive motor 210.
The driving force transmission gears 2102, 21
It is mounted on a carriage 2120 that engages with a spiral groove 2121 of a lead screw 2104 that rotates via a guide screw 2104, and reciprocates in the directions of arrows a and b along a guide 2119 together with the carriage 2120 by the power of the drive motor 2101. Be moved. The paper pressing plate 2105 for the recording paper P that is conveyed onto the platen 2106 by a recording medium feeding device (not shown) presses the recording paper P against the platen 2106 in the carriage movement direction.

Reference numerals 2107 and 2108 denote photocouplers, which are home position detecting means for confirming the presence of the lever 2109 of the carriage 2120 in this area and switching the rotation direction of the drive motor 2101. 2110
Reference numeral 2112 is a support member that supports the cap member 2111 that caps the entire surface of the recording head 2110 described above. Reference numeral 2112 is suction means that sucks the inside of the cap member 2111, and performs suction recovery of the recording head 2200 through the opening 2113 in the cap. . 2114 is a cleaning blade, 21
Reference numeral 15 denotes a moving member that allows the blade to move in the front-rear direction, and these are supported by the main body support plate 2116. Needless to say, the cleaning blade 2114 is not limited to this type and a known cleaning blade can be applied to this embodiment.

Further, reference numeral 2117 is a lever for starting suction for suction recovery, which moves in accordance with the movement of the cam 2118 engaging with the carriage 2120, and the drive motor 2101.
Movement of the driving force from the vehicle is controlled by known transmission means such as clutch switching. A recording control unit that gives a signal to the heating unit 2110 provided in the recording head 2200 and controls the drive of each mechanism described above is provided on the recording apparatus main body side (not shown).

In the ink jet recording apparatus 2100 having the above-mentioned structure, the recording head 2200 reciprocates over the entire width of the recording sheet P with respect to the recording sheet P conveyed onto the platen 2106 by the recording medium feeding apparatus. Since recording is performed and the recording head 2200 manufactured by the method described above is used, high-accuracy and high-speed recording is possible.

Further, the ink jet recording apparatus has an electric signal applying means for applying an electric signal for ejecting ink to the recording head. Further, the inkjet recording apparatus is not limited to the above-described mode for recording on a recording medium, and is also a printing apparatus for recording a pattern on a cloth or the like for recording. In this printing apparatus, since recording is continuously performed on a long piece of cloth, the ink jet recording head provided with the heating resistor of the present invention is unlikely to cause deterioration of recording quality due to wire breakage during recording or large fluctuation of resistance value. The application is particularly desirable.

The present invention is particularly effective in a recording head and a recording apparatus of the type which ejects ink by utilizing thermal energy, which is proposed by Canon Inc. among ink jet recording systems.

With regard to its typical structure and principle, see, for example, US Pat. Nos. 4,723,129 and 4,4.
What is done using the basic principles disclosed in 740,796 is preferred.

This system is applicable to both the so-called on-demand type and continuous type, but in particular,
In the case of the on-demand type, the electrothermal converter arranged corresponding to the sheet or liquid path holding the liquid (ink) corresponds to the recorded information and has a rapid temperature rise exceeding nucleate boiling. By applying at least one drive signal that gives a heat energy to the electrothermal converter, the film is boiled on the heat-acting surface of the recording head, and as a result, the liquid (ink It is effective because bubbles can be formed inside. The liquid (ink) is ejected through the ejection openings by the growth and contraction of the bubbles to form at least one droplet. It is more preferable to make the driving signal into a pulse shape because bubbles can be grown and contracted immediately and appropriately, and thus a liquid (ink) with excellent responsiveness can be ejected. This pulse-shaped drive signal is described in U.S. Pat. No. 4,463,359 and U.S. Pat.
Those as described in 345,262 are suitable. If the conditions described in US Pat. No. 4,313,124 relating to the rate of temperature rise of the heat acting surface are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the ejection port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned respective specifications. The present invention also includes configurations using US Pat. No. 4,558,333 and US Pat. No. 4,459,600, which disclose configurations in which a heat acting portion is arranged in a bending region. It is a thing. In addition, Japanese Unexamined Patent Publication No. 59-123670 discloses a structure in which a common slit is used as a discharge portion of a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy is discharged. The present invention is also effective in a structure based on Japanese Patent Laid-Open No. 59-138461 which discloses a structure corresponding to a part.

Further, as a full line type recording head having a length corresponding to the maximum recording medium width that can be recorded by the recording apparatus, the length can be increased by combining a plurality of recording heads as disclosed in the above-mentioned specification. The present invention can exert the above-mentioned effects more effectively, although it may have a configuration that satisfies the above requirements or a configuration as one recording head integrally formed.

In addition, by being attached to the apparatus main body, it can be electrically connected to the apparatus main body and can be supplied with ink from the apparatus main body by a replaceable chip type recording head or the recording head itself. The present invention is also effective when a cartridge-type recording head that is specially provided is used.

Further, it is preferable to add recovery means for the recording head, preliminary auxiliary means, etc., which are provided as a constitution of the recording apparatus of the present invention, because the effects of the present invention can be further stabilized. . Specific examples thereof include capping means, cleaning means, pressurization or suction means, an electrothermal converter or a heating element other than this, a preheating means for the recording head, and a recording head for the recording head. It is effective to perform a preliminary ejection mode in which another ejection is performed for stable recording.

Further, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but the recording head may be integrally formed or a plurality of combinations may be used. Alternatively, the present invention is extremely effective for an apparatus provided with at least one of full colors by color mixing.

In the embodiments of the present invention described above, the ink is described as a liquid, but it is an ink that solidifies at room temperature or lower, and is softened or liquid at room temperature, or the ink itself is 30 in the above ink jet. It is common to adjust the temperature within a range of ℃ to 70 ℃ to control the temperature of the ink so that the viscosity of the ink is in a stable ejection range. Good. In addition, it is possible to prevent the temperature rise due to thermal energy from being positively used as the energy for changing the state of the ink from the solid state to the liquid state, or to use the ink that solidifies when left standing for the purpose of preventing ink evaporation. In any case, due to the heat energy, such as ink that is liquefied by the application of heat energy according to the recording signal and ejected as an ink liquid, or that has already started to solidify when it reaches the recording medium. The use of an ink having a property of liquefying for the first time is also applicable to the present invention. In such a case, the ink is disclosed in JP-A-54-56.
No. 847 or Japanese Patent Application Laid-Open No. 60-71260, such that it faces the electrothermal converter in the state of being held as a liquid or solid in the recesses or through holes of the porous sheet. May be In the present invention, the most effective ones for the above inks are
The film boiling method described above is executed.

[0039]

EXAMPLES The present invention will now be described in more detail based on more specific examples.

Generally, the applied voltage to the heating element is 1.2 times the Vth when the level at which film boiling starts is Vth, and the upper limit is 1.3. However, when the heating element material is HfB ₂ , when it is used with a K value of 1.3,
Normally, it is not possible to obtain the same life as the life of the printer main body capable of recording 20,000 sheets, and furthermore, when ink is ejected by driving the double heater, the life of the HfB ₂ heating element becomes shorter and shorter. There is a limit to the commercialization of a replaceable head having a relatively short service life in which the tank and the head are integrated and the number of recordable sheets is limited. A more preferred embodiment using the heating resistor of the present invention will be described, including the advantages of the present invention under the use condition of the recording head.

As shown in the X-ray diffraction pattern (I) of FIG. 8, the heating resistor of the present invention has Ta as a main crystal.
It has a peak of N _{0.8 hex} . Here, considering preferable conditions of the composition ratio x of Ta and N, TaN _{0.8 hex}
When the value of the x value of Ta _x N is 1.05 or more and 1.85 or less as a resistor having, TaN _{0.8 hex} which is the X-ray diffraction pattern of FIG. 9 and Ta ₂ which is the X-ray diffraction pattern of FIG. Three crystal structures of N _hex and TaN _{hex + cubic} were obtained as shown in Table 1.

[0042]

[Table 1] As shown in Table 1, the value of each composition ratio x of Ta and N in each obtained crystal structure is EPMA (electron probe microanalyzer), more preferably RBS (Rutherford Ba).
ckscattering spectrometry) and each crystal structure is X
Determined by the line diffraction method, TaN _{0.8 hex} , Ta ₂ N
Each quantitative ratio (mol%) of _hex and TaN _{hex + cubic} is calculated. In addition, the value of each composition ratio x was determined using the same sample.
It was performed by measuring the number of times and averaging the measured values. In the bottom column of Table 1, the numbers of corresponding examples described below are shown.

Example 1 A substrate for an ink jet recording head having the structure shown in FIG. 1 was manufactured as follows. First, immediately before film formation, the substrate surface was cleaned by plasma cleaning in the same apparatus. Heat storage layer 1
As the heat storage layer 103, SiO ₂ having a thickness of 1.2 μm is formed by a thermal oxidation method as 02, and the heat storage layer 103 also serves as interlayer insulation.
SiON was deposited to a thickness of 1.2 μm by the plasma CVD method.

Next, as the resistance layer 104, the value of the composition ratio x of Ta _x N was set to x = 1.25, and as shown in FIG. 8 (X-ray diffraction pattern (I)), TaN _{0.8 hex} as a crystal was formed. A film showing only the peak (TaN _{0.8 hex} 100 mol%) was formed in a thickness of 1000 angstrom. The TaN
_{The 0.8 hex} film has a nitrogen gas partial pressure ratio of 24%, a total pressure of a mixed gas of argon gas and nitrogen gas of 7.5 mTorr, a sputtering DC power of 2.0 kW, an ambient temperature of 200 ° C., and a substrate by a reactive sputtering method. Temperature is 20
The film was formed under the condition of 0 ° C. On this TaN _{0.8 hex} film,
Al, which is a conductor for supplying thermal energy generated for ejecting ink, was deposited to a thickness of 5500 angstrom by a sputtering method. The Al
The layer was continuously formed by sputtering in the same apparatus after the heating resistor was deposited and before being taken out into the atmosphere. By this continuous film formation, the resistance layer and the Al wiring were prevented from invading impurities and moisture, and the recording head substrate having good adhesion between both layers and high reliability could be manufactured. Then, the Al layer and the TaN _{0.8 hex} layer were patterned into a predetermined shape. The heat acting portion 108 is a region where the Al layer on the TaN _{0.8 hex} layer is removed as shown in FIG. Next, as the protective film 106, SiN is deposited to a thickness of 1 μm by the plasma CVD method, and then, as the cavitation resistant layer 107, a Ta film is deposited to the thickness of 2000 angstrom by the DC sputtering method, and the present invention is performed. The ink jet recording head substrate was completed.

Here, the heat storage layer 103 and the protective film 106 are formed by using the same plasma CVD film forming apparatus while controlling the film forming conditions to predetermined conditions, and the resistance layer 104 and the cavitation resistant layer 107 are also the same. Using the same Ta target in the reactive sputtering film-forming apparatus of No. 2, two kinds of films were formed by controlling the film-forming conditions to predetermined conditions. As a result, the number of film forming devices is small, and the contamination in the device is small,
Furthermore, batch opening has been reduced as much as possible, enabling a production process with high yield and high availability.

FIG. 11 shows the results of the SST test performed.
Indicated. The SST test refers to the ink ejection Vth
The applied voltage is increased every 0.05 Vth and 100,000 pulses each
Is applied to obtain a breaking voltage Kb. In Figure 11
TaN of Example 1 in_{0.8 hex} The film was used as a heating resistor
In this case, the change in resistance value of the electrothermal converter is extremely small.
The breakdown voltage ratio K_b (K_b = Applied voltage / foaming voltage)
Was found to have good characteristics of 1.8 Vth
It was

FIG. 12 shows the maximum drive voltage of 1.3 Vt.
The result of the heat pulse endurance test (CST test) at h is shown. In the CST test, only a pulse is applied to the heating resistor, and no ink is contained in the recording head. From the results of this experiment, it was found that the electrothermal converter using the TaN _{0.8 hex} film of Example 1 had a resistance value change of almost 0%.

Next, the results of a print endurance test conducted by manufacturing a head including the heating resistor of Example 1 and mounting it on an ink jet recording apparatus will be described. The test was carried out by printing a general test print pattern incorporated in the inkjet recording apparatus on A4 paper. The drive voltage at this time was adjusted to be 1.3 Vth. As shown in Table 2, the TaN _{0.8 hex of} Example 1 has a print life of 1500 characters per page and is a standard document with 2
It is possible to print more than 50,000 sheets, and the print quality is shown in Fig. 13 which shows the resistance change at the end of printing.
And, as shown in Table 2, the long endurance test was performed at 20,000
The print quality did not deteriorate even after printing 0 sheets. This 20,0
The printing durability life of 00 sheets is almost the same as the printer body life.

The number of applied pulses of the nozzle to which the maximum pulse is applied per page of a standard document of 1500 characters is
It is about 3 × 10 ⁴ pulses. Therefore, in order to print 20,000 sheets, the number of applied pulses is 5 × 10 ^{8 to} 6 × 1 in consideration of the life reduction due to continuous ejection.
0 durability to withstand the application of the ⁸ pulses so that the suffices.

Example 2 TaN of Example 1_0.8 hex To
In place of the resistance layer 104 composed of
The composition was 1.85 and the X-ray diffraction pattern as shown in FIG.
TaN indicating a turn _0.8 hex And Ta₂ N_hex Mixed of
The heating resistor of Example 2 was prepared and used to
A jet print head was manufactured. 11 SST test
As shown in the results, in Example 2, the breaking voltage ratio K_b Is 1.
It was a good result of 8 Vth. Also, the CST of FIG.
As shown in the test results, the change in resistance is (−) side (resistance
The life is shorter than that of the first embodiment because the value decreases.
5 x 10⁸ The heating element was broken by the pulse, but recorded
When evaluated as a head, as shown in FIG.
Is capable of printing at least 10,000 sheets
It was At that time, the print quality did not deteriorate until it was broken.
won.

[Embodiment 3] In place of the resistance layer made of TaN _{0.8 hex} of Embodiment 1, the x value in Table 1 is 1.05.
The heating resistor of Example 3 was prepared as a tantalum nitride film in which TaN _hex and TaN _hex having the composition of FIG. 10 and having an X-ray diffraction pattern as shown in FIG. Was produced. S in FIG.
As shown in the ST test result, in the third embodiment, the breaking voltage ratio K
_b was 1.8 Vth, which was a good result. In addition, FIG.
As shown in the CST test result of Example 3, it was found that in Example 3, the change in the resistance value was changed to the (+) side (change in which the resistance value was increased), and when evaluated as a recording head,
As shown in FIG. 13, it was found that printing of 20,000 sheets or more was possible.

[Examples 4 to 7] A heating resistor made of TaN _{0.8 hex} and Ta ₂ N in Table 1 having a TaN _0.8 mixed molar ratio of 80% was used in Example 4, and a TaN _0.8 mixed molar ratio of 50% was used. A resistor is used in Example 5, and TaN _{0.8 hex} and T are used.
The TaN _0.8 mixing mol ratio of the heating resistor by aN is 80.
% Resistor in Example 6, TaN _0.8 mixed molar ratio of 50.
% Of the resistor as Example 7 and FIG. 13 shows the results of the printing durability test of each Example. The test results of Example 4 and Example 5 were found to show the characteristics between Example 1 and Example 2. Further, it was found that the test results of Example 6 and Example 7 show the characteristics between Example 1 and Example 3. Therefore, the mixing molar ratio of TaN _0.8 is 50%.
From the above, it was found that the effects of the present invention can be more stably exhibited, and a more ideal resistor and inkjet head can be provided.

Next, the actual number of printed sheets in these examples is summarized in Table 2 below.

[0054]

[Table 2] In the print durability test results in Table 2, the number of print durable sheets is
It is the number of prints until the heating resistor is disconnected. Regarding the image quality, generally, the resistance value of the heating resistor increases as the number of characters printed increases, the current flowing through the resistor decreases, the heating energy decreases, and as a result, the life is extended. However, the reduction in the current flowing through the heating resistor reduces the heat generation energy, and as a result, the amount of ink ejected decreases, which may cause print deterioration such that the print density becomes low.

As can be seen from Table 2, the heating element of Example 1 is
Printing was possible on more than 20,000 sheets, and there was no deterioration in quality. That is, it was found that the inkjet recording head using TaN _{0.8 hex of} Example 1 was excellent in recorded image quality and durability, and was suitable for long life and high image quality.

The heating element of Example 2 does not have a durable life up to the life of the printer body, but is effective as a heating element for a replaceable head that is replaced every 10,000 sheets, and has image quality performance. I understand.

In the case of the heating element of Example 3, although the image quality deteriorates, it has a durability life equal to or more than that of a normal commercial printer having a printing life of about 20,000 sheets, and is very good in terms of durability. It was found that the ink-jet recording head had characteristics, and although the image density was slightly reduced, the resistance value increased, and it was found that the ink-jet recording head was suitable as a permanent ink jet recording head.

Further, each of the heating elements of Examples 4 to 7 is capable of printing 20,000 sheets or more and has no deterioration in quality, which is the same as that of Example 1 described above. , And more specifically, TaN _0.8 mixed mol
It was found that the higher the ratio, the closer to the good characteristics of Example 1.

From the above points, a recording head using a heating element which is a mixture of TaN _0.8 and Ta ₂ N and has a mixing molar ratio of TaN _0.8 of 50% or more does not change the resistance value of the resistor. Although visible, even if 20,000 sheets were printed, there was no image deterioration due to the breakage of the heating element and recording, and it was found that a normal commercial printer can be used in the same manner as in Example 1. When the mixing ratio of TaN _0.8 is 80% or more, the resistance value changes, but the characteristic difference from Example 1 cannot be confirmed.

In a recording head using a heating element which is a mixture of TaN _0.8 and TaN and has a mixing molar ratio of TaN _0.8 of 50% or more, a change in the resistance value of the resistor can be seen. It was found that even if 20,000 sheets were printed, there was no breakage of the heating element and no image deterioration, and a normal commercial printer can be used in the same manner as in Example 1. T
When the mixing ratio of aN _0.8 is 80% or more, the resistance value changes, but the characteristic difference from Example 1 cannot be confirmed.

Further, from the results shown in Table 2, it is found that each heating resistor of the recording head having a large number of heating resistors is
It has been found that even when the resistors of Examples 1 to 7 described above are mixed and used, they can be used as an exchangeable recording head without any problem.

Here, as in the second and third embodiments,
Ta ₂ which has TaN _0.8 but is conventionally known
Consider a resistor including N and TaN. In general, Ta ₂ used as a material for conventional tantalum nitride heating elements
It has been found that the mixture of N, TaN and Ta ₂ N / TaN does not have durability performance as an inkjet recording head due to a large change in resistance value as described in the prior art. The mechanism of these resistance changes is Ta
It is expected that ₂ N is oxygen from other film layers due to the application of a pulse of high electric energy, and Ta, which is a surplus of NO _x , becomes a metal, and the Ta metal lowers the resistance value. It is also expected that TaN takes in oxygen in the vicinity by pulse application and becomes TaO + TaN polycrystal, increasing the resistance value. Further, the mixture of Ta ₂ N / TaN seems to exhibit the characteristic that the resistance change is canceled and the resistance value does not change.
resistance change due to a ₂ N, since the larger the resistance value decreases with the square operation by applying energy increasing resistance decrease in itself and due to it, the resistance value variation characteristic, the characteristic of the Ta ₂ N is appeared dominantly, the As a result, it is expected that the resistance value changes such that the resistance value increases with an increase in pulse application due to printing.

[0063] For these conventional heating elements, resistors having the above-described TaN _{0.8 hex} the present invention, as can be expected from the behavior the result of the change in resistance value, TaN _{0.8 hex} is against application of the drive pulse , A crystal structure that suppresses the oxidation or reduction of Ta, and as a result, the unique resistance value change obtained by the present invention, which cannot be predicted from the conventional heating element without TaN _{0.8 hex} , is expected. Recognized as showing. Therefore, it can be said that the tantalum nitride film in which TaN _{0.8 hex} can be detected by the measurement by the X-ray diffraction method is stable against the impressed pulse.

From the above points, it is understood that the tantalum nitride film is suitable as the material of the heating resistor for the double heater of the multi-valued ink jet recording head due to the difference in the film structure, and TaN _{0.8 according} to the present invention is used. It has been found that the heat-generating resistor containing the material is excellent as a heat-generating resistor for an ink jet recording head.

Further, the drive element of the double heater is N-
It has been found that by using a MOS transistor, even if the density is 900 DPI or higher, it can be laid out on the substrate at a density higher than that of the heat generating elements, so that it can be efficiently laid out on the substrate.

[0066]

In the ink jet recording head having the double heater heating resistor having TaN _0.8 of the present invention, the heating resistor has a very small variation in the resistance value even if it is continuously used for a long time, and has a long life. There is an effect that it can be made highly reliable and high density and high quality recording can be made possible.

Further, in the ink jet recording head according to the present invention, a multi-valued head having a high density of 900 DPI or more can be constructed by using the N-MOS transistor as the driving element of the double heater.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of an inkjet recording head substrate of the present invention.

FIG. 2 is a schematic layout of a double heater of the present invention.

FIG. 3 is an equivalent circuit of the ink jet recording head substrate of the present invention.

FIG. 4 is a schematic cross-sectional view of a main element of a substrate for an inkjet recording head of the present invention which is longitudinally cut.

FIG. 5 is a schematic perspective view of an inkjet recording head of the present invention.

FIG. 6 is a schematic cross-sectional view of a double pulse drive foaming of an inkjet recording head substrate of the present invention.

FIG. 7 is a schematic perspective view showing an example of an inkjet recording apparatus using the recording head of the present invention.

8 is an X-ray diffraction measurement pattern of the resistance layer forming the TaN _0.8 heating resistor in Example 1. FIG.

9 is an X-ray diffraction measurement pattern in Example 2. FIG.

10 is an X-ray diffraction measurement pattern in Example 3. FIG.

FIG. 11 is a diagram showing the results of the SST test in Examples 1 to 3.

FIG. 12 is a diagram showing results of CST tests in Examples 1 to 7.

FIG. 13 is a diagram showing the results of a print durability test in Examples 1 to 7.

[Explanation of symbols]

101 Silicon substrate 102 thermal oxide film 103 Interlayer film 104 Resistance layer 105 Al alloy wiring 106 protective film 107 Anti-cavitation film 108 Heat acting part 601 ink discharge liquid 602 foam 603 ink 604 Drive means

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-8395 (JP, A) JP-A-7-125218 (JP, A) JP-A-2-6138 (JP, A) JP-A-3- 224741 (JP, A) JP-B-62-48585 (JP, B1) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41J 2/05

Claims (7)

(57) [Claims] 1. A heat generating resistor is provided in one nozzle .
In the substrate used in the ink jet recording head is a multi-value output head double heater is provided, the double
The heating resistor of the heater has a TaN _0.8 crystal structure.
And the two heating resistors are adjacent with a gap of several μm.
A substrate for an ink jet recording head, characterized in that 2. A heat generating resistor is provided in one nozzle .
In a multi-valued output head provided with a double heater , in an ink jet recording head for recording ink on a recording medium by ejecting ink from a discharge port by using heat energy from the heat generating resistor, the heat generating resistor of the double heater is Ta.
Look including the crystal structure of N _0.8, and two heating resistors is several μ
An inkjet recording head characterized in that they are adjacent to each other with a gap of m . 3. The ink jet recording head according to claim 2 , wherein the heating resistor has a crystal structure of only TaN _0.8 . 4. The heating resistor is TaN _0.8 or TaN.
The ink jet recording head according to claim 2 , comprising an N crystal structure. 5. The heating resistor comprises TaN _0.8 and TaN.
The inkjet recording head according to claim 2 , wherein the inkjet recording head includes a ₂ N crystal structure. 6. The driving transistor of the heating element is NM
Ink jet recording head according to any one of claims 2-5 is an OS transistor. 7. A ink jet recording head according to any one of claims 2-6 in which the discharge port is provided for ejecting ink to a recording surface of the recording medium, for mounting the head An inkjet recording apparatus comprising at least a member.