JPS61285687A - Manufacture of heat generating body - 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 [Technical Field] The present invention relates to a method for manufacturing a heating element, and particularly to a method for manufacturing a heating element provided with a protective layer.

[Prior art and its problems]

Heat generating elements such as thermal heads are widely used in computers, printers such as word processors, and the like. This type of heating element must be sufficiently insulating, heat resistant, or abrasion resistant since it undergoes thermal shock and slides against printed paper. Therefore, conventional technology uses complex film formation techniques to form resistive heating elements, electrodes, wiring, and protective films.
It was necessary to perform etching, etc., which required a large number of steps and a large manufacturing cost. A typical thin film forming method for a thermal head involves forming a glaze layer as a heat retaining layer on a substrate surface, and then performing the following film forming process.

t Deposition of heating element 2 Deposition of electrode/wiring 3゜ Patterning of electrode/wiring 4 Patterning of heating element & Formation/processing of wear-resistant layer On top of such a complicated process, as a film-forming device, requires a large investment in equipment because it uses sputtering, vapor deposition, chemical vapor deposition (CVD), etc. Therefore, if even one of the film forming steps can be omitted, it is expected to be a great advantage in terms of the manufacturing process.

Further, as a characteristic problem, unless the film formation and patterning of the heating element are strictly controlled, a constant resistance value cannot be stably provided. Therefore, there is a need for a means for easily controlling the characteristics of the heating element to provide desired characteristics.

[Purpose of the invention]

Accordingly, an object of the present invention is to provide a method for manufacturing a heat generating element such as a thermal head using fewer steps. An additional object of the present invention is to provide a method of manufacturing a heating element in which the resistance of the heating element can be easily controlled and with fewer steps.

[Summary of structure and effects of the invention]

The method for manufacturing a heating element of the present invention includes forming two layers, a film for electrodes/wiring and an insulating or wear-resistant film, and forming a structure of the two layers in a region where a heating resistor is to be formed (heating part). It consists of converting substances into a predetermined heating resistor by diffusing them into each other. Here, the constituent materials of the electrode/wiring film and the wear-resistant film are selected from those that can form a resistor by diffusion. In a preferred method, the diffusion step, that is, the step of forming the heating resistor, can be performed while applying a voltage between the electrodes and measuring the resistance value.

According to the method of the present invention, there is no need to separately form a heat generating part, and the heat generating part can be created simply by performing a diffusion process such as annealing, thereby reducing the number of film forming processes and reducing manufacturing costs. becomes possible.

In addition, as a preferable example, if the resistance value is measured during the process of forming the heat generating part, the formation of the heat generating part can be completed when a predetermined resistance value is achieved, so that the heat generating part has a strictly controlled resistance value. can be provided.

[Detailed description of the invention]

1 to 4 show sequential steps of the method for manufacturing a heating element of the present invention. Figure 1 shows the process of forming electrodes and wiring. First, a glaze layer 1 is formed on a suitable substrate, and then a metal, such as 'l
'i, AI, Cr, Fe, Ni, Co
One or more layers 2 of at least one metal or alloy selected from 5Cu, Mo, WSNi-Cr, Zr, Ta, etc. are formed. Since this metal is determined relative to the composition of the wear-resistant film, it is selected in accordance with the composition of the heating resistor to be formed.

Next, a metal layer 3 having etching characteristics different from that of the metal of layer 2 is formed on layer 1 2 . For example, a highly conductive metal such as AI or Cu can be used to provide the main portions of the electrodes and wiring.

FIG. 2 shows the buttering process. That is, metal layer 3
The portion 4 is removed in a predetermined pattern by any method such as dry etching to expose the underlying metal layer 2.

FIG. 5B is a plan view showing how a plurality of heating elements are formed simultaneously. The portion of the metal layer 2 exposed to the removed portion 4 is a portion that should become a heat generating portion.

Moving to the step shown in FIG. 3, a wear-resistant film 5 is formed to cover the removed portion 4 and the electrode/wiring portion 3. The material of this membrane is 5
in2, Al 20. , B P , 5iBxOy.

TiC, TiN, SiC, B4C5SiCxNy
, 5iOxCyNz.

Ta, 05, SiOxNy, 5iOxCy,
Select from 5iA1ON. These materials must be capable of forming a predetermined heating resistor between them and the metal layer 2 by diffusion.

Finally, in the process shown in FIG. 4, a diffusion treatment is performed to form the heating resistor layer 6. That is, a laser beam or a hot ray 7 is applied to the metal layer 2 through the removal section 4 . This locally heats the interface between the metal layer 2 and the wear-resistant layer 5 and causes diffusion, resulting in a material having a different resistance value from both of these layers. This diffusion layer, that is, the heating resistor layer 6 is a resistor that is the same as or similar to a known cermet. Resistor layer 6 has properties intermediate between layers 2 and 5. Furthermore, the resistance value can be adjusted by controlling the diffusion process. For example, as shown in FIG. 4, probes 8 are applied to both sides of the removed portion 40 of the electrode layer 3 to apply a voltage, and a resistance meter 9 is used to monitor changes in resistance value during the diffusion process. As soon as a predetermined resistance value is achieved, laser annealing is stopped and the diffusion process is completed.

According to this method, a heating element such as a thermal head having a precisely controlled arbitrary resistance value can be obtained.

Next, an example will be described.

EXAMPLES A heating element was manufactured by the method described above. The metal layer is Ti
was deposited to a thickness of 300 layers, and on top of that a film of AI was deposited to a thickness of 7,000 layers. AI was removed so that the length of the removed portion 4 was 200 μm. Further, the width was set to 100 μm. As the wear-resistant layer 5, 5iOBN was formed to a thickness of 5 μm, and then the removed portion 4 was irradiated with a laser beam. At that time, changes in electrical resistance were monitored. The resistance value rose to 800Ω. By adjusting the laser beam irradiation time, the resistance value can be reduced to 3.
It was found that it can be freely set within the range of 00 to 800Ω. The resistance layer 6 formed by diffusion has changed into a type of cermet.

〔Effect of the invention〕

As described above, according to the present invention, it is sufficient to form two layers: the electrode/wiring and the insulating or wear-resistant layer, and the heating resistance layer can be formed by diffusion between these two layers. Therefore, it is possible to reduce the cost by reducing the number of film forming steps. Furthermore, since the resistance change can be measured during the diffusion process, there is an advantage that a heating element with constant characteristics can be easily produced. Furthermore, by changing the laser temperature, the thickness of the metal layer 2, the laser irradiation time, etc., an arbitrary resistance value can be obtained. Thus, the method of the present invention has the advantage of being highly flexible and easy to control.

[Brief explanation of drawings]

1 to 4 show sequential steps showing one example of the method of the present invention, in which FIG. 1 is a cross section, FIG. 2(a) is a cross section, and FIG. 2(b) is a cross section.
) shows a plane, FIG. 3 shows a cross section, and FIG. 4 shows a cross section. 1: Glaze layer 2: Metal layer (material that can become a resistor by diffusion) 3: Electrode
Wiring metal layer 4: removed portion

Claims (1)

[Claims] 1. Forming on the substrate a metal layer that constitutes at least a part of the electrode wiring and that can be converted into a predetermined heating resistor by interdiffusion with the insulating or wear-resistant layer described later; The insulating or wear-resistant layer is formed thereon, and then the area where the heating resistor is to be formed is locally heated to cause the metal layer and a part of the insulating or wear-resistant layer to interdiffuse, thereby forming the heating resistor. A method for manufacturing a heating element, which comprises converting into a heating element. 2. The method for manufacturing a heating element according to item 1 above, wherein the local heating is performed while measuring the electrical resistance of the region.