JPH0611548B2 - Method of manufacturing thermal head - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a thermal head.

2. Description of the Related Art In a conventional thin film thermal head, as shown in FIG. 3A, a so-called glaze-alumina substrate 3 having a smooth glass layer 2 on a ceramic substrate 1 such as alumina is mainly used. This is the strength, smoothness,
This is because, in terms of heat resistance and the like, the properties required for the thermal head are well satisfied, and it is relatively inexpensive as compared with other materials such as quartz. Also, by adjusting the thickness of the glass layer appropriately, the thermal response speed of the thermal head,
The thermal efficiency can be improved. Therefore, the glass layer 2 is
Must be formed. On the glazed alumina substrate 3, as disclosed in Japanese Patent Laid-Open No. 53-51753, SiO _{2 is used} as an electrical insulating layer 4 which is less likely to be etched than the glass layer ₂ .
A layer made of Al ₂ O ₃ , Cr ₂ O ₃ , SnO ₂ , Si ₃ N ₄ , BN, SiC, etc. was formed, and a thin film heating resistor 5 and conductive thin film layers 6 and 7 were sequentially laminated on this layer. After that, a wiring pattern is formed, for example, as shown in the sectional view c of FIGS. 3B and 3B.

By the way, the normal thin-film heating resistor 5 includes Ta ₂ N, Ta-SiO ₂ , Cr-Si-O, titanium carbide, silicon,
Some of them consist of oxygen, but all of them are removed by an HF + HNO ₃ based etching solution as an etching solution that is usually used, so that the thin film heating resistor 5 is directly formed on the glass layer 2 without forming the electrically insulating layer 4. When formed and patterned as shown in FIGS. 3b and 3c, the surface of the glass layer 2 is corroded (etched) as shown in FIG. Resistor 5, conductive thin film layer 6,
7 penetrates up to the glass layer 2 in the portion where the thin film heating resistor 5 is etched, and it is difficult to control the resistance value with high precision, and the life of the heating element deteriorates. In addition, there arises a problem that the external circuit does not have sufficient strength for connection, for example, bonding. Therefore, conventionally, the electrically insulating layer 4 has been required as an etching prevention layer. This electrically insulating layer 4 has no particularly positive meaning other than the effect as the above-mentioned etching prevention layer, and is usually formed continuously in the same device as the heating resistor, so that the electrically insulating layer 4 is not formed. There is a problem in that the residual impurities when forming No. 4 may affect the heating resistor that follows, and the process becomes complicated.

Among the problems as described above, particularly in order to speed up the thermal recording, a large effect can be obtained by using a thin film heating resistor made of titanium carbide, silicon and oxygen.

Problems to be Solved by the Invention As described above, when a thin film heating resistor made of titanium carbide, silicon and oxygen is used for speeding up of the thermal head, a conventional HF + HNO ₃ based etching solution is used for pattern formation. Then, the glass layer coated on the surface of the substrate is etched, causing various problems. Therefore, it is necessary to form an electrically insulating etching prevention layer between the glass layer and the thin film heating resistor.

From this point of view, the present invention uses a thin film heating resistor made of titanium carbide, silicon, and oxygen for speeding up the thermal head, and uses an appropriate etching solution for the thin film heating resistor to provide an electrically insulating etching prevention layer. It is an object of the present invention to provide a method for manufacturing a thermal head that eliminates the need for.

Means for Solving the Problems In order to solve the above problems, the present invention provides a heating resistor composed of titanium carbide, silicon, and oxygen as a mixed solution containing ammonia water and hydrogen peroxide water as main components. This is a method of manufacturing a thermal head in which a pattern is formed by etching.

Operation With the above-mentioned configuration, the heating resistor composed of titanium carbide, silicon, and oxygen is a mixed solution containing ammonia water and hydrogen peroxide water as the main components, and can be stably etched to form a good pattern. Since the mixed solution does not attack the glass, a good pattern can be formed without forming an electrically insulating etching prevention layer, and the process can be simplified.
It is possible to configure a method of manufacturing a thermal head that is excellent in safety and extremely effective in practical use, without using a solution that is extremely harmful to the human body.

Example 1 Example 1 FIG. 1 shows an example of the basic configuration of a method for manufacturing a thermal head according to the present invention. As shown in FIG. 5A, for example, titanium carbide, silicon, and the like are formed on a so-called glaze-alumina substrate 11 in which a glass glaze layer 10 is formed on an alumina substrate 9.
As a heating resistor made of oxygen, a TiC-SiO ₂ thin film heating resistor 12 is formed, and a conductive thin film layer, for example, 2
Form what consists of layers. Of these, the first conductive thin film layer
13 is Cr, and the second conductive thin film layer 14 is Au or C.
After u is sequentially laminated and formed as u, for example, a wiring pattern is formed as shown in FIG. At this time, the TiC-SiO ₂ thin film heating resistor 12 was used as a solution containing NH ₄ OH: H ₂ O ₂ : EDTA (ethylenediaminetetraacetic acid): H ₂ O = 24 cc as a mixture of ammonia water and hydrogen peroxide water as main components. : 75cc: 3g:
Etching was performed using a 120 cc one. Here, EDTA is a chelating agent, and H ₂ O is also used for diluting the solution and is not always necessary. As a result, the TiC-SiO ₂ thin-film heating resistor can form a good pattern, does not corrode the glass glaze layer surface 15, and can form a highly reliable pattern, thereby forming an electrically insulating etching prevention layer. There is no need to form. By the way, FIG. 1c shows the etching characteristics 16 of the solution containing the ammonia water and the hydrogen peroxide solution as the main components. In the figure, the horizontal axis represents the ratio of the actual etching time to the time (= just etching time) at which the TiC-SiO ₂ thin film heating resistor 12 is etched, and the vertical axis represents the TiC-SiO ₂ thin film heating. The side etching amount of the TiC—SiO ₂ thin film heating resistor 12 is indicated by the difference in the pattern width between the resistor 12 and the first conductive thin film (Cr) 13 that serves as a mask during this etching. From the figure, the side etching amount is at most about 0.5 μm even if it is etched 4 times, and it is at most about 2 times the etching during normal manufacturing, so there is almost no side etching, and it has extremely excellent etching characteristics. It turns out that it has.

Embodiment 2 In particular, the present invention has been recently developed in order to improve the quality of the image surface and the mass productivity of a color printer, for example, Japanese Patent Application No. 58-12.
In the case of No. 8314, that is, as shown in FIG. 2, a TiC-SiO ₂ heating resistor 19 is provided on one end surface 18 of the substrate 17, and a separation electrode 20 for energizing the TiC-SiO ₂ heating resistor 19 is provided on the main plane 21 of the substrate 17. Is particularly effective when a three-dimensional pattern is required, such as forming the common electrode 22 on the other main plane 23, and at this time, in order to prevent abnormal formation of the electrodes, particularly the separation electrodes 20, at least glass. The glaze layer 24 is connected to the separation electrode 20.
And the TiC-SiO ₂ heating resistor 19 must be formed on the one main plane 21 and the end face 18. When a conventional HF + HNO ₃ based etching solution is used, an etching prevention layer is formed on the glass glaze layer 24. Since it has to be formed on the one main plane 21 and the end surface 18 that form the above, it does not lead to improvement in productivity, and that is achieved only by using a solution in which ammonia water and hydrogen peroxide water are mixed as main components. it can.

Although TiC-SiO ₂ was used as the heating resistor composed of titanium carbide, silicon, and oxygen in Examples 1 and 2, the etching solution containing ammonia water and hydrogen peroxide water as the main components was TiC-SiO _2.
Since it acts on C, the same effect can be obtained also by a combination of TiC—Si—SiO _{2 and the} like. Further, the etching solution containing ammonia water and hydrogen peroxide as the main components does not necessarily have to have the mixing ratio of this embodiment, and depending on the composition and combination of the heating resistor, if an appropriate mixing ratio is selected, The same effect can be obtained.

As described above, according to the present invention, a heating resistor made of titanium carbide, silicon and oxygen for increasing the speed of a thermal head is etched with a mixed solution containing ammonia water and hydrogen peroxide water as main components. In the method of manufacturing a thermal head, which is characterized by forming a pattern, a good pattern can be formed without forming an electrically insulating etching prevention layer, the process can be simplified, and a highly safe manufacturing process is possible. Can be assembled and is extremely effective in practice.

[Brief description of drawings]

FIG. 1 is a diagram for specifically explaining an improvement regarding etching in an example of a method for manufacturing a thermal head of the present invention, and FIG. 2 is a diagram for explaining an embodiment in which the present invention is particularly effective. , FIG. 3 is an explanatory view of a conventional example. 16 ... An example of etching characteristics of a mixed solution of the present invention containing ammonia water and hydrogen peroxide water as main components.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kiyoharu Yamashita 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-52-109947 (JP, A)

Claims (1)

[Claims] 1. A method of manufacturing a thermal head, characterized in that a heating resistor made of titanium carbide, silicon and oxygen is etched and patterned by a mixed solution containing ammonia water and hydrogen peroxide water as main components. Method.