JP7413066B2 - Thermal print head manufacturing method, thermal print head and thermal printer - Google Patents

Description

The present disclosure relates to a method of manufacturing a thermal print head, a thermal print head, and a thermal printer.

Patent Document 1 discloses an example of a conventional thermal print head. A thermal print head generally includes a large number of heat generating parts arranged in the main scanning direction on a head substrate. Each heat generating part is formed by laminating an upstream conductive layer and a downstream conductive layer on a resistor layer formed on the head substrate via a heat storage layer so as to expose a part of the resistor layer. There is. By passing current between the upstream electrode layer and the downstream electrode layer, the exposed portion (heat generating portion) of the resistor layer generates heat due to Joule heat. The heat storage layer is formed to store the heat generated by the heat generating part, and enables high-speed printing.

In the thermal print head disclosed in Patent Document 1, Si (silicon) is used as a base material, and each component including a resistor layer is formed by a semiconductor process. In this case, the heat storage layer is formed by sputtering or CVD using SiO ₂ (silicon dioxide). Steps such as sputtering need to be repeated depending on the required thickness of the heat storage layer. Therefore, it takes a considerable amount of time to form a heat storage layer of a thickness necessary for higher speed printing, and there is a problem that the manufacturing efficiency of the thermal print head deteriorates.

Further, Patent Document 2 also discloses a thermal print head using Si as a base material. In the thermal print head disclosed in Patent Document 2, the base material has a main surface and a convex portion extending in the main scanning direction and protruding from the main surface. As shown in FIG. 6 of the same document, the plurality of heat generating parts are arranged in the main scanning direction on the convex part. According to such a configuration, the printing medium can be accurately brought into contact with the convex portion where the plurality of heat generating portions are arranged, and an improvement in print quality can be expected. It is desirable to appropriately arrange the heat storage layer even in such a convex portion that forms a part of the base material and in which a plurality of heat generating portions are arranged.

JP 2017-7203 Publication JP2019-166824A

The present disclosure was devised under the above circumstances, and it is possible to appropriately arrange a heat storage layer (glaze) between a convex portion formed on a base material and a heat generating portion. An object of the present invention is to provide a method for manufacturing a thermal print head, a thermal print head, and a thermal printer.

A method for manufacturing a thermal print head provided by a first aspect of the present disclosure includes a step of preparing a base material made of a single crystal semiconductor, and a glaze made of a glass material extending in the main scanning direction on the base material. an anisotropic etching step of performing anisotropic etching on the base material using the glaze as a mask; and forming a plurality of heat generating parts arranged in the main scanning direction on the glaze. In the anisotropic etching step, a main surface facing one side in the thickness direction and a top surface protruding from the main surface and covered with the glaze are formed on the base material. A convex portion having a convex portion is formed.

A thermal print head provided by a second aspect of the present disclosure has a main surface facing one side in the thickness direction, and is formed on a base material made of a single crystal semiconductor, and on the main surface, and is configured to perform main scanning. a resistor layer including a plurality of heat generating parts arranged in a direction; an insulating layer formed between the base material and the resistor layer; and a resistor layer formed between the base material and the plurality of heat generating parts. , a glaze made of a glass material, the base material having a convex portion protruding from the main surface and extending in the main scanning direction, and the convex portion having a top surface parallel to the main surface. However, the glaze covers the top surface.

A thermal printer provided by a third aspect of the present disclosure includes the thermal print head according to the second aspect of the present disclosure, and a platen disposed opposite to the plurality of heat generating parts.

According to the present disclosure, the glaze can be appropriately placed between the convex portion formed on the base material and the heat generating portion.

Other features and advantages of the present disclosure will become more apparent from the detailed description given below with reference to the accompanying drawings.

FIG. 1 is a plan view showing a thermal print head according to a first embodiment of the present disclosure. FIG. 2 is an enlarged plan view of main parts of the thermal print head shown in FIG. 1. FIG. FIG. 2 is an enlarged plan view of main parts of the thermal print head shown in FIG. 1. FIG. 2 is a cross-sectional view taken along line IV-IV in FIG. 1. FIG. 5 is a partially enlarged view of FIG. 4. FIG. 6 is a partially enlarged view of FIG. 5. FIG. FIG. 2 is a cross-sectional view showing one step in an example of a method for manufacturing the thermal print head shown in FIG. 1. FIG. FIG. 8 is a cross-sectional view showing a step following FIG. 7; FIG. 9 is a cross-sectional view showing a step following FIG. 8; 10 is a cross-sectional view showing a step subsequent to FIG. 9. FIG. 11 is a cross-sectional view showing a step following FIG. 10. FIG. FIG. 12 is a cross-sectional view showing a step subsequent to FIG. 11; FIG. 13 is a cross-sectional view showing a step following FIG. 12; FIG. 14 is a cross-sectional view showing a step following FIG. 13; FIG. 15 is a cross-sectional view showing a step subsequent to FIG. 14; FIG. 2 is a cross-sectional view showing one step of another example of the method for manufacturing the thermal print head shown in FIG. 1; FIG. 17 is a cross-sectional view showing a step following FIG. 16; FIG. 18 is a cross-sectional view showing a step following FIG. 17; 19 is a cross-sectional view showing a step following FIG. 18. FIG. FIG. 20 is a cross-sectional view showing a step following FIG. 19; FIG. 2 is a cross-sectional view showing one step of another example of the method for manufacturing the thermal print head shown in FIG. 1; FIG. 22 is a cross-sectional view showing a step following FIG. 21; FIG. 23 is a cross-sectional view showing a step subsequent to FIG. 22; 24 is a cross-sectional view showing a step subsequent to FIG. 23. FIG. FIG. 25 is a cross-sectional view showing a step following FIG. 24; 26 is a cross-sectional view showing a step following FIG. 25. FIG. 7 is a sectional view similar to FIG. 6 showing a modification of the thermal print head shown in FIG. 1. FIG. FIG. 7 is a cross-sectional view similar to FIG. 6 showing a thermal print head according to a second embodiment of the present disclosure. 29 is a cross-sectional view showing one step in the method for manufacturing the thermal print head shown in FIG. 28. FIG. 30 is a cross-sectional view showing a step following FIG. 29. FIG. 31 is a cross-sectional view showing a step subsequent to FIG. 30. FIG. FIG. 32 is a cross-sectional view showing a step following FIG. 31; 33 is a cross-sectional view showing a step following FIG. 32. FIG. 34 is a cross-sectional view showing a step subsequent to FIG. 33. FIG. FIG. 35 is a cross-sectional view showing a step subsequent to FIG. 34; FIG. 7 is a cross-sectional view similar to FIG. 6 showing a thermal print head according to a third embodiment of the present disclosure. 37 is a cross-sectional view showing one step in the method for manufacturing the thermal print head shown in FIG. 36. FIG. FIG. 38 is a cross-sectional view showing a step following FIG. 37; 39 is a cross-sectional view showing a step following FIG. 38. FIG. 40 is a cross-sectional view showing a step following FIG. 39. FIG.

Hereinafter, preferred embodiments of the present disclosure will be specifically described with reference to the drawings.

In this disclosure, "a thing A is formed on a thing B" and "a thing A is formed on a thing B" mean "a thing A is formed on a thing B" unless otherwise specified. "It is formed directly on object B," and "It is formed on object B, with another object interposed between object A and object B." Similarly, "something A is placed on something B" and "something A is placed on something B" mean "something A is placed on something B" unless otherwise specified. This includes ``directly placed on object B'' and ``placed on object B with another object interposed between object A and object B.'' Similarly, "a certain object A is located on a certain object B" means, unless otherwise specified, "a certain object A is in contact with a certain object B, and a certain object A is located on a certain object B." ``The fact that a certain thing A is located on a certain thing B while another thing is interposed between the certain thing A and the certain thing B.'' In addition, "a certain object A overlaps a certain object B when viewed in a certain direction" means, unless otherwise specified, "a certain object A overlaps all of a certain object B" and "a certain object A overlaps with a certain object B". This includes "overlapping a part of something B."

<First embodiment>
1 to 6 show a thermal print head according to a first embodiment of the present disclosure. The thermal print head A1 of this embodiment includes a head substrate 1, a connection substrate 5, a plurality of wires 61 and 62, a plurality of driver ICs 7, a protective resin 78, and a heat dissipation member 8. The thermal print head A1 is installed in a printer that prints on a print medium (not shown) that is conveyed by a platen roller 99 (see FIG. 4). Examples of print media include thermal paper for creating barcode sheets and receipts. Note that in place of the platen roller 99, a platen that is not roller-shaped may be used. This platen has a flat surface. Flat surfaces include curved surfaces with small curvature. In this disclosure, the platen roller and the platen having a flat surface are collectively referred to as a platen. The thermal printer of the present disclosure includes the thermal print head of the present disclosure and a platen.

FIG. 1 is a plan view showing the thermal print head A1. FIG. 2 is an enlarged plan view of the main parts of the thermal print head A1. FIG. 3 is an enlarged plan view of the main parts of the thermal print head A1. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. FIG. 5 is a sectional view of a main part of the thermal print head A1, and is an enlarged sectional view of a part of FIG. 4. FIG. 6 is an enlarged cross-sectional view of a main part of the thermal print head A1, and is a cross-sectional view in which a part of FIG. 5 is enlarged. In FIGS. 1 to 3, for convenience of understanding, a protective layer 2, which will be described later, is omitted. In FIGS. 1 and 2, the protective resin 78 is omitted for convenience of understanding. Further, in FIG. 2, the wire 61 is omitted for convenience of understanding. Further, in these figures, description will be made assuming that the longitudinal direction (main scanning direction) of the head substrate 1 is the x direction, the lateral direction (sub scanning direction) is the y direction, and the thickness direction is the z direction. Regarding the y direction, the lower side of Figures 1 to 3 (the right side of Figures 4 to 6) is defined as the "upstream" where the print medium is fed, and the upper side of Figures 1 to 3 (the right side of Figures 4 to 6) (on the left) is defined as the "downstream" where the print media is ejected. Regarding the z direction, the upper side of FIGS. 4 to 6 (the direction pointed by the arrow indicating direction z) is defined as "upper", and the opposite direction is defined as "lower". The same applies to the following figures.

As shown in FIG. 4, in the thermal print head A1, the head substrate 1 and the connection substrate 5 are mounted adjacent to each other in the y direction on the heat dissipation member 8. A plurality of heat generating parts 41 arranged in the y direction are formed on the head substrate 1 according to a configuration that will be explained in detail later. The heat generating unit 41 is selectively driven to generate heat by a driver IC 7 mounted on the connection board 5, and is pressed against the heat generating unit 41 by a platen roller 99 in accordance with a print signal transmitted from the outside via a connector 59. Print on the medium.

The head substrate 1 includes a base material 10, a glaze 15, an insulating layer 19, a protective layer 2, an electrode layer 3, and a resistor layer 4, as shown in FIGS. 1 to 6.

The base material 10 is made of a single crystal semiconductor. Si is suitable as the single crystal semiconductor. As shown in FIG. 1, the base material 10 has an elongated rectangular shape with the x direction as the longitudinal direction and the y direction as the lateral direction when viewed in the z direction. The size of the base material 10 is not limited, but to give an example, the dimension in the x direction is, for example, 50 mm or more and 150 mm or less, the dimension in the y direction is, for example, 1.0 mm or more and 5.0 mm or less, and the dimension in the z direction is, for example, For example, it is about 725 μm. In the base material 10, the side closer to the driver IC 7 in the y direction is the upstream side, and the side farther from the driver IC 7 is the downstream side. The print medium is conveyed by the platen roller 99 from the upstream side to the downstream side in the y direction.

The base material 10 has a main surface 11 and a convex portion 12, as shown in FIGS. 1, 2, 5, and 6. The main surface 11 faces upward in the z direction. In the present disclosure, the main surface 11 is a plane that extends along the xy plane (a plane defined by the x direction and the y direction, and the same applies to other planes) and is substantially parallel to the xy plane. The main surface 11 is a (100) plane. The convex portion 12 protrudes from the main surface 11 in the z direction and extends in the x direction. The convex portion 12 is formed on the downstream side of the main surface 11. The convex portion 12 has a cross-sectional shape along the yz plane that is uniform in the x direction. Hereinafter, a cross section along the yz plane will be referred to as a "yz cross section." The convex portion 12 has a dimension W1 in the y direction at the lower end in the z direction of, for example, about 500 μm, and a dimension W2 in the y direction at the upper end in the z direction (top surface 121 described later) is, for example, 200 μm. That's about it. Further, the dimension H1 of the convex portion 12 in the z direction is, for example, about 150 μm.

As shown in FIGS. 5 and 6, the convex portion 12 has a top surface 121 and a pair of inclined outer surfaces 122. The top surface 121 is parallel to the main surface 11 and is substantially flat. The top surface 121 has an elongated rectangular shape that extends in the x direction when viewed in the z direction. The dimension H1 is the distance between the top surface 121 and the main surface 11 in the z direction.

A pair of inclined outer surfaces 122 sandwich the top surface 121 in the y direction. Further, the pair of inclined outer surfaces 122 are connected to the main surface 11 and the top surface 121, respectively, and are sandwiched between them in the y direction. Each inclined outer surface 122 is inclined with respect to the main surface 11 and the top surface 121 such that the farther from the top surface 121 in the y direction, the lower the surface becomes. In other words, as the pair of inclined outer surfaces 122 move away from the main surface 11 in the z direction (as they move upward in the figure), they approach each other in the y direction. Each inclined outer surface 122 is substantially flat. The inclination angle α1 of each inclined outer surface 122 with respect to the main surface 11 is, for example, 54.8 degrees. Each inclined outer surface 122 is a (111) plane.

The glaze 15 is made of a glass material such as amorphous glass, and functions as a heat storage layer. The glaze 15 is formed, for example, by firing a glass paste. In this embodiment, the coefficient of thermal expansion of the glaze 15 is approximately the same as that of Si, which is the material of the base material 10. Note that the characteristics of the glass material of the glaze 15 are not limited. As shown in FIGS. 5 and 6, the glaze 15 is placed on the convex portion 12. As shown in FIG. The glaze 15 is in contact with the top surface 121 and covers the entire top surface 121. In this embodiment, the glaze 15 is not in contact with the inclined outer surface 122. The glaze 15 extends in the x direction and is formed over the entire width of the top surface 121 in the y direction. That is, the glaze 15 covers the entire top surface 121 in the cross section viewed along the x direction (main scanning direction).

In this embodiment, as shown in the manufacturing method described below, the glaze 15 is formed by repeating twice the process of disposing and heating glass paste. Specifically, the first glaze is formed on the base material by disposing and heating (preliminary firing) the glass paste (first glass paste) for the first time. Then, a second glass paste (second glass paste) is placed on the first glaze. Here, the second glass paste is placed on top of the first glaze, so the second glass paste is placed so that the dimension in the z direction is larger (for example, about 3 times) than the first glass paste in the first application. can. That is, in this embodiment, the glaze 15 is formed to be overwhelmingly thicker (for example, about 4 times) than when it is formed by disposing and firing (heating) the glass paste once. In this embodiment, the second glass paste placed the second time has the same composition as the first glass paste placed the first time. Therefore, the glaze 15 has no boundaries and is integrated. Note that the details of the manufacturing method will be described later.

In this embodiment, the thickness of the glaze 15 (dimension H2 in the z direction) is, for example, 30 μm or more and 200 μm or less (preferably 30 μm or more and 50 μm or less). Further, the ratio of the dimension H2 in the z direction to the width (dimension W2 in the y direction) of the glaze 15 (so-called aspect ratio) is 0.05 or more and 0.2 or less. In this embodiment, since the glaze 15 is formed over the entire width of the top surface 121 in the y direction, the width of the glaze 15 is the width of the top surface 121 (dimension in the y direction), that is, the width above the convex portion 12 in the z direction. It is the same as the dimension W2 in the y direction at the side end. Note that the dimensions of the glaze 15 are not limited. The thickness (dimension H2) and width (dimension W2) of the glaze 15 are designed so that it can sufficiently store heat and not store too much heat unnecessarily. If the required thickness (or aspect ratio) is small, the glaze 15 may be formed by placing and baking (heating) the glass paste in one step.

As shown in FIG. 6, a pair of round portions 151 are formed on the upper surface of the glaze 15 at both ends in the y direction. The pair of round portions 151 are each curved portions that are raised. Due to the pair of round parts 151, the surface of the glaze 15 is smoothly continuous over each inclined outer surface 122 of the convex part 12. Each round portion 151 is formed by firing the glass paste when forming the glaze 15. In the example shown in FIG. 6, the upper surface of the glaze 15 has a shape in which a substantially flat surface is interposed between a pair of round portions 151 in the y direction. Note that the upper surface of the glaze 15 may not have this substantially flat surface and may have a shape in which a pair of round portions 151 are connected to each other. In this case, the upper surface of the glaze 15 becomes a convex surface curved upward in the z direction.

The insulating layer 19 is formed on the main surface 11 of the base material 10 and covers the base material 10 and the glaze 15, as shown in FIGS. 5 and 6. The insulating layer 19 is in contact with the main surface 11 , the pair of inclined outer surfaces 122 of the convex portion 12 , and the upper surface of the glaze 15 . The insulating layer 19 is for more reliably insulating the base material 10 from the resistor layer 4 and the electrode layer 3. The insulating layer 19 may be formed in the region of the base material 10 where the resistor layer 4 or the electrode layer 3 is formed. The insulating layer 19 is made of an insulating material, such as SiO ₂ or SiN (silicon nitride), preferably TEOS-SiO ₂ (SiO ₂ formed from TEOS (tetraethyl orthosilicate) as a raw material). . The thickness of the insulating layer 19 is not particularly limited, and is, for example, 1 μm or more and 10 μm or less.

The resistor layer 4 is formed on the insulating layer 19 and covers the insulating layer 19, as shown in FIGS. 5 and 6. The resistor layer 4 is formed across the main surface 11 and the convex portion 12 with an insulating layer 19 in between. The resistor layer 4 is made of TaN (tantalum nitride), for example. The thickness of the resistor layer 4 is not particularly limited, and is, for example, 0.02 μm or more and 0.1 μm or less (preferably about 0.08 μm).

The resistor layer 4 includes a plurality of heat generating parts 41, as shown in FIGS. 3, 5, and 6. The plurality of heat generating parts 41 are portions of the resistor layer 4 that are not covered with the electrode layer 3 described later and are exposed. The plurality of heat generating units 41 locally heat the print medium by selectively energizing each of them. The plurality of heat generating parts 41 are arranged in the x direction and spaced apart from each other in the x direction. The formation area of the plurality of heat generating parts 41 in the y direction is an area including a part or all of the top surface 121 of the convex part 12 in the y direction. Therefore, each heat generating portion 41 overlaps the glaze 15 when viewed in the z direction. Note that the platen (for example, the platen roller 99 shown in FIG. 4) is arranged to face each heat generating part 41 extending along the x direction.

The electrode layer 3 constitutes a conduction path for supplying electricity to the plurality of heat generating parts 41. The electrode layer 3 is laminated on the resistor layer 4 and supported on the base material 10. The electrode layer 3 is made of a metal material having a resistance value smaller than that of the resistor layer 4, and is made of, for example, Cu (copper). The thickness of the electrode layer 3 is not particularly limited, and is, for example, 0.3 μm or more and 2.0 μm or less. Note that the electrode layer 3 may have a structure in which a Cu layer and a Ti (titanium) layer are laminated. In this case, the Ti layer is interposed between the Cu layer and the resistor layer 4, and has a thickness of, for example, about 100 nm.

The electrode layer 3 includes a plurality of individual electrodes 31 and a common electrode 32, as shown in FIGS. 1 to 3, 5, and 6. A portion of the resistor layer 4 exposed from the electrode layer 3 between the plurality of individual electrodes 31 and the common electrode 32 serves as a plurality of heat generating parts 41 . The shapes of each individual electrode 31 and common electrode 32 when viewed in the z direction, that is, the formation areas of each individual electrode 31 and common electrode 32 are not limited to the examples shown in FIGS. 1 and 2.

Each of the plurality of individual electrodes 31 has a band shape extending approximately in the y direction. Each individual electrode 31 is arranged upstream of each heat generating part 41 in the y direction. As shown in FIGS. 3 and 6, in this embodiment, the tip of each individual electrode 31 on the downstream side in the y direction extends to above the inclined outer surface 122 on the upstream side in the y direction. An electrode pad portion 311 is formed at the tip of each individual electrode 31 on the upstream side in the y direction. The electrode pad portion 311 is a portion connected to the driver IC 7 mounted on the connection board 5 by a wire 61.

The common electrode 32 includes a common portion 323 and a plurality of comb teeth portions 324, as shown in FIGS. 2 and 3. The common portion 323 connects the plurality of comb teeth portions 324 in common. The common portion 323 extends in the x direction. The common portion 323 is located downstream of the plurality of comb teeth portions 324 in the y direction. Each comb tooth portion 324 has a band shape extending from the upstream edge of the common portion 323 in the y direction. The plurality of comb teeth portions 324 are spaced apart from each other and lined up in the x direction. The tip of each comb tooth portion 324 on the upstream side in the y direction is opposed to the tip of each individual electrode 31 at a predetermined interval. Therefore, the resistor layer 4 is exposed from the electrode layer 3 between the tip of each comb tooth portion 324 on the upstream side in the y direction and the tip of each individual electrode 31 on the downstream side in the y direction. As shown in FIGS. 3 and 6, the tip of each comb tooth portion 324 on the upstream side in the y direction extends above the inclined outer surface 122 on the downstream side in the y direction. The y-direction downstream portion of each comb tooth portion 324 and the common portion 323 are formed on the main surface 11, as shown in FIG.

The protective layer 2 covers the electrode layer 3 and the resistor layer 4, as shown in FIGS. 5 and 6. The protective layer 2 is made of an insulating material, such as SiO ₂ , SiN, SiC (silicon carbide), AlN (aluminum nitride), or a laminate of two or more thereof. The thickness of the protective layer 2 is not particularly limited, and is, for example, 1.0 μm or more and 10 μm or less. In the thermal printer, the protective layer 2 that overlaps each heat generating part 41 when viewed in the thickness direction of the base material 10 can be pressed against one surface of the printing medium. The other side of the print medium with the protective layer 2 pressed onto it can be pressed against a platen (eg platen roller 99 shown in FIG. 4).

As shown in FIG. 5, the protective layer 2 has a pad opening 21 penetrating in the z direction. The pad openings 21 expose the electrode pad portions 311 provided on the plurality of individual electrodes 31, respectively.

As shown in FIGS. 1 and 4, the connection board 5 is disposed adjacent to the head board 1 on the upstream side in the y direction. The connection board 5 is, for example, a PCB board. For example, as shown in FIG. 1, the connection board 5 has an elongated rectangular shape with the x direction as the longitudinal direction when viewed in the z direction. As shown in FIG. 4, the connection board 5 is equipped with a driver IC 7 and a connector 59.

Connector 59 is used to connect thermal print head A1 to a printer (not shown). As shown in FIG. 4, the connector 59 is attached to the connection board 5 and connected to a wiring pattern (not shown) on the connection board 5.

The driver IC 7 is mounted on the connection board 5, as shown in FIGS. 1 and 4, and energizes the plurality of heat generating parts 41 individually. The driver IC 7 is connected to each electrode pad portion 311 of each individual electrode 31 by a plurality of wires 61, as shown in FIGS. 4 and 5. Further, the driver IC 7 is connected to a wiring pattern formed on the connection board 5 by a plurality of wires 62. Print signals and control signals transmitted from the outside via the connector 59 and voltages supplied to the plurality of heat generating parts 41 are input to the driver IC 7 . The plurality of heat generating parts 41 are individually energized in accordance with the print signal and the control signal to selectively generate heat.

The driver IC 7 and the plurality of wires 61, 62 are covered with a protective resin 78 formed so as to span the head substrate 1 and the connection substrate 5, as shown in FIGS. 4 and 5. The protective resin 78 is made of a black insulating material such as epoxy resin.

As shown in FIG. 4, the heat radiating member 8 supports the head substrate 1 and the connection substrate 5, and is provided to radiate part of the heat generated by the plurality of heat generating parts 41 to the outside. The heat radiation member 8 is made of metal such as aluminum.

Next, an example of a method for manufacturing the thermal print head A1 will be described below with reference to FIGS. 7 to 15. 7 to 15 are cross-sectional views showing one step of the method for manufacturing the thermal print head A1, and correspond to the cross-section shown in FIG. 6.

First, as shown in FIG. 7, a base material 10A is prepared. The base material 10A is made of a single crystal semiconductor, and is, for example, a Si wafer. The base material 10A has a main surface 11A. The main surface 11A is substantially flat and faces upward in the z direction. The principal surface 11A is a (100) plane. This step corresponds to the "step of preparing a base material" of the present disclosure.

Next, as shown in FIGS. 8 to 10, a glaze 15 is formed.

In the step of forming the glaze 15 (glaze forming step), first, as shown in FIG. 8, a glass paste (first glass paste 15A) is placed on the main surface 11A of the base material 10A and heated. In this embodiment, the first glass paste 15A is placed by applying the glass paste onto the base material 10A using a dispenser (not shown). The first glass paste 15A is arranged in an elongated rectangular shape extending in the x direction when viewed in the z direction. The region where the first glass paste 15A is placed corresponds to the top surface 121 of the convex portion 12 that will be formed later. After that, the first glass paste 15A is heated (temporary firing). The heating temperature (first heating temperature) of the first glass paste 15A is, for example, about 300°C. As a result, first glaze 15B is formed. In this embodiment, the first glass paste 15A is adjusted so that the coefficient of thermal expansion of the first glaze 15B after firing is approximately the same as that of Si, which is the material of the base material 10. Note that the composition of the first glass paste 15A is not limited.

Next, as shown in FIG. 9, a glass paste (second glass paste 15C) is placed on the first glaze 15B. The second glass paste 15C is placed by applying (discharging) the glass paste using a dispenser (not shown). The second glass paste 15C is arranged in an elongated rectangular shape extending in the x direction when viewed in the z direction. In this application, since the second glass paste 15C is placed on the first glaze 15B, the dimension in the z direction is made larger than in the case of the first application in which the first glass paste 15A is placed on the base material 10A. (for example, about 3 times as much), the second glass paste 15C can be placed. In other words, in this embodiment, the glaze 15 can be formed overwhelmingly thicker (for example, about 4 times) than when it is formed by applying the glass paste once and firing it.

Thereafter, by heating (baking) the second glass paste 15C, a second glaze 15D is formed as shown in FIG. The first glaze 15B is softened by the firing, and the glaze 15 is formed by combining with the second glaze 15D formed by firing the second glass paste 15C. Here, the temperature (second heating temperature) when heating (firing) the second glass paste 15C is, for example, about 850°C or about 1200°C, and the heating temperature (first heating temperature) of the first glass paste 15A. The temperature is higher than that of An appropriate firing temperature is selected depending on the composition of the second glass paste 15C. In this embodiment, the second glass paste 15C placed in the second application has the same composition as the first glass paste 15A placed in the first application. Therefore, the glaze 15 formed by the second heating (firing) is integrated. In addition, in FIG. 10, for convenience, the boundary between the first glaze 15B and the second glaze 15D is shown by a broken line. Note that the second glass paste 15C disposed for the second time may have a different composition from the first glass paste 15A disposed for the first time. The glaze 15 has round portions 151 formed at both ends of its surface in the y direction.

As described above, the glaze 15 is formed by repeating the process of coating and heating the glass paste twice. Note that the glass paste may be arranged by printing using a screen. In other words, screen printing may be used to place the glass paste. Screen printing can also be used in other embodiments.

Next, as shown in FIG. 11, convex portions 12 are formed. The convex portions 12 are formed by performing anisotropic etching on the base material 10A using the glaze 15 formed on the main surface 11A as a mask. In the process of forming the convex portions 12, for example, anisotropic etching using an alkaline aqueous solution is performed. Examples of this alkaline aqueous solution include KOH (potassium hydroxide) and TMAH (tetramethylammonium hydroxide). Thereby, as shown in FIG. 11, a base material 10 having a main surface 11 and a convex portion 12 is formed. The main surface 11 is a (100) plane like the main surface 11A. The convex portion 12 has a top surface 121 and a pair of inclined outer surfaces 122. The entire top surface 121 is covered with the glaze 15. Each of the pair of inclined outer surfaces 122 is a (111) plane, and is inclined with respect to the main surface 11 and the top surface 121. The inclination angle α1 of each inclined outer surface 122 is, for example, 54.8 degrees. The process of forming the protrusion 12 corresponds to the "anisotropic etching process" of the present disclosure.

Next, as shown in FIG. 12, an insulating layer 19 is formed. The insulating layer 19 is formed by depositing TEOS-SiO ₂ using, for example, CVD. The insulating layer 19 covers the main surface 11 , the pair of inclined outer surfaces 122 of the convex portion 12 , and the glaze 15 .

Next, as shown in FIG. 13, a resistor film 4A is formed. The resistor film 4A is formed by, for example, forming a thin film of TaN on the insulating layer 19 by sputtering. The resistor film 4A covers the entire surface of the insulating layer 19.

Next, as shown in FIG. 14, a conductive film 3A is formed. The conductive film 3A is formed by forming a layer made of Cu by, for example, plating or sputtering. The conductive film 3A covers the entire surface of the resistor film 4A. Note that in forming the conductive film 3A, a structure may be adopted in which a Ti layer is formed on the insulating layer 19 and then a Cu layer is formed.

Next, as shown in FIG. 15, the conductive film 3A and the resistor film 4A are partially removed by selectively etching the conductive film 3A and the resistor film 4A. As a result, a resistor layer 4 separated in the x direction, and a plurality of individual electrodes 31 and a common electrode 32 that cover the resistor layer 4 while leaving a plurality of heat generating parts 41 are formed. The process of forming the resistor film 4A, forming the conductive film 3A, and partially removing the conductive film 3A and the resistor film 4A corresponds to the "heat generating part forming process" of the present disclosure.

Next, a protective layer 2 is formed. The protective layer 2 is formed by depositing, for example, SiN on each of the insulating layer 19, the electrode layer 3, and the resistor layer 4 using, for example, CVD. Thereafter, the protective layer 2 is partially removed by etching or the like in order to form the pad opening 21.

Next, the base material 10 is cut along the x direction and the y direction to divide it into individual pieces. Through the above steps, the head substrate 1 is obtained. Then, by assembling the head board 1 and the connection board 5 onto the heat dissipation member 8, mounting the driver IC 7 on the connection board 5, bonding the plurality of wires 61 and 62, and forming the protective resin 78, as shown in FIG. The thermal print head A1 shown in FIGS. 1 to 6 is manufactured.

Next, the operation of this embodiment will be explained.

In manufacturing the thermal print head A1 of this embodiment, a glaze 15 extending in the x direction (main scanning direction) is formed on the base material 10A, and then, using the glaze 15 as a mask, the base material 10A, which is a single crystal semiconductor, is coated. Perform anisotropic etching. Thereafter, a plurality of heat generating parts 41 arranged in the x direction are formed on the glaze 15. In the step of performing anisotropic etching using the glaze 15 as a mask, the base material 10 is formed with a main surface 11 facing upward in the z-direction and a convex portion 12 protruding from the main surface 11 in the z-direction. . The convex portion 12 has a top surface 121 that is parallel to the main surface 11 , and the entire top surface 121 is covered with the glaze 15 .

According to this embodiment, relative positional displacement in the y direction between the convex portion 12 and the glaze 15 disposed on the convex portion 12 (top surface 121) can be suppressed. Therefore, the convex portion 12 and the glaze 15 disposed on the convex portion 12 (particularly its cross-sectional shape as viewed along the x direction) are different from each other on the upstream and downstream sides in the y direction (the transversal direction of the base materials 10, 10A, etc.). The sides are balanced, and it is possible to suppress variations in print quality of the thermal print head A1. Furthermore, since the convex portion 12 is formed by performing anisotropic etching on a single crystal semiconductor, its yz cross section is approximately uniform in the x direction (longitudinal direction of the base materials 10, 10A, etc.). Become. That is, the pressing contact state of the print medium with the heat generating portion 41 is approximately constant at various locations in the x direction. This does not change even if the manufacturing lot of the head substrate 1 is different, and is suitable for suppressing variations in printing quality.

According to this embodiment, the glaze 15 is formed by repeating the steps of placing and heating the glass paste twice. Since the second glass paste (second glass paste 15C) is placed on the first glaze 15B, it is placed so that the dimension in the z direction is larger than that of the first glass paste (first glass paste 15A). can. Therefore, the glaze 15 is formed to be much thicker than when it is formed by disposing and firing (heating) the glass paste once. According to such a configuration, the glaze 15 can appropriately store the heat generated by each heat generating part 41, and the heat storage effect of the glaze 15 can be improved.

According to the present embodiment, since the entire top surface 121 is covered with the glaze 15, the glaze 15 and a pair of inclined outer surfaces connected to the glaze 15 are formed in a cross section viewed along the x direction (main scanning direction). 122 are smoothly connected to each other. As a result, the insulating layer 19, the resistor film 4A, the conductive film 3A, and the protective layer 2, which are formed in this order on the glaze 15 and the pair of inclined outer surfaces 122, are smoothly formed. Therefore, the insulating layer 19, resistor layer 4, electrode layer 3, and protective layer 2 that the thermal print head A1 has are formed smoothly, so the yield (good product rate) when manufacturing the thermal print head A1 is improved. improves.

Furthermore, in this embodiment, the heating temperature of the first glass paste 15A (first heating temperature) is lower than the heating temperature of the second glass paste 15C (second heating temperature). In the present embodiment, the first glaze 15B formed after heating the first glass paste 15A has a regular shape but is not sufficiently fired, so it does not have predetermined characteristics. After that, by placing the second glass paste 15C on the first glaze 15B and heating (baking), a first glaze 15B originating from the first glass paste 15A and a second glaze 15D originating from the second glass paste 15C are formed. Together, the glaze 15 having predetermined characteristics is formed. Therefore, when forming the glaze 15 by repeating the process of placing and heating the glass paste twice, the time required to form the glaze 15 can be shortened by varying the temperature conditions during heating as described above. , the manufacturing efficiency of the thermal print head A1 can be improved.

Next, another example of the method for manufacturing the thermal print head A1 will be described below with reference to FIGS. 16 to 20. 16 to 20 are cross-sectional views showing one step of the method for manufacturing the thermal print head A1, and correspond to the cross-section shown in FIG. 6. Note that in these figures, descriptions of steps that are the same as or similar to those described with reference to FIGS. 7 to 15 are omitted as appropriate.

The manufacturing method shown in FIGS. 16 to 20 differs mainly in the method of forming the glaze 15 compared to the method for manufacturing the thermal print head A1 described with reference to FIGS. 7 to 15 above.

In this manufacturing method, in the step of forming the glaze 15 (glaze forming step), first, as shown in FIG. 16, a screen 91 is placed on the main surface 11A side of the prepared base material 10A. The screen 91 is a thin metal plate (metal mask) in which a slit 91a, which is an opening penetrating in the z direction, is formed. The slit 91a is formed in an elongated rectangular shape that extends in the x direction when viewed in the z direction. The width (dimension in the y direction) S1 of the slit 91a is approximately the same as the width (dimension in the y direction) of the top surface 121 of the convex portion 12 that will be formed later.

Next, a glass paste (first glass paste 15A) is printed on the base material 10A using a screen printing technique. As a result, the first glass paste 15A is placed only at the position passing through the slit 91a on the base material 10A. After that, the screen 91 is removed. Next, by heating (pre-baking) the first glass paste 15A, a first glaze 15B is formed as shown in FIG. 17. In this embodiment, the first glass paste 15A is adjusted so that the coefficient of thermal expansion of the first glaze 15B after firing is approximately the same as that of Si, which is the material of the base material 10. Note that the composition of the first glass paste 15A is not limited. "Screen printing" includes both the use of metal masks and the use of mesh screens.

Next, as shown in FIG. 18, a screen 93 is placed on the main surface 11A side of the base material 10A. The screen 93 is a metal plate (metal mask) in which a slit 93a, which is an opening penetrating in the z direction, is formed. The slit 93a is formed in an elongated rectangular shape that extends in the x direction when viewed in the z direction. The width (dimension in the y direction) S2 of the slit 93a is slightly smaller than the width (dimension in the y direction) S1 of the slit 91a shown in FIG. It is less than 90%. Note that the relationship between the width S1 of the slit 91a and the width S2 of the slit 93a is not limited to this. In this embodiment, a spacer 92 is attached to the screen 93 on the surface facing the base material 10A. The spacer 92 is made of resin, for example, and is located between the main surface 11A of the base material 10A and the lower surface of the screen 93 when the screen 93 is placed on the base material 10A. Note that the spacer 92 does not need to be attached.

Next, a glass paste (second glass paste 15C) is printed on the base material 10A using a screen printing technique. Thereby, as shown in FIG. 19, the second glass paste 15C is placed on the first glaze 15B formed on the base material 10A. In this printing, the second glass paste 15C is placed on the first glaze 15B, so the dimension in the z direction is made larger than in the first printing in which the first glass paste 15A is placed on the base material 10A. (for example, about 3 times as much), the second glass paste 15C can be placed. That is, in this embodiment, the glaze 15 can be formed to be overwhelmingly thicker (for example, about 4 times) than when formed by one-time screen printing and baking. Thereafter, screen 93 (and spacer 92) is removed. At this point, the second glass paste 15C has a substantially uniform thickness when viewed in the x direction, and has a rectangular yz cross section.

Thereafter, by heating (baking) the second glass paste 15C, a second glaze 15D is formed as shown in FIG. 20. The first glaze 15B is softened by the firing, and the glaze 15 is formed by combining with the second glaze 15D formed by firing the second glass paste 15C. In this embodiment, the second glass paste 15C placed in the second screen printing has the same composition as the first glass paste 15A placed in the first screen printing. Therefore, the glaze 15 formed by the second heating (firing) is integrated. Note that in FIG. 20, for convenience, the boundary between the first glaze 15B and the second glaze 15D is shown by a broken line. Note that the second glass paste 15C placed in the second screen printing may have a different composition from the first glass paste 15A placed in the first screen printing. The glaze 15 has round portions 151 formed at both ends of its surface in the y direction.

As described above, the glaze 15 is formed by repeating the process of placing glass paste by printing and heating it twice.

Thereafter, in the same manner as described above with reference to FIGS. 11 to 15, formation of the convex portion 12 (anisotropic etching step), formation of the insulating layer 19, formation of the resistor film 4A, and formation of the conductive film 3A. The formation, partial removal of the conductive film 3A and the resistor film 4A (heat generating part forming step), and division of the base material 10 into individual pieces are performed in this order. Thereby, the head substrate 1 is obtained. Then, by assembling the head board 1 and the connection board 5 onto the heat dissipation member 8, mounting the driver IC 7 on the connection board 5, bonding the plurality of wires 61 and 62, and forming the protective resin 78, as shown in FIG. The thermal print head A1 shown in FIGS. 1 to 6 is manufactured.

Also in this manufacturing method, relative positional deviation in the y direction between the convex portion 12 and the glaze 15 disposed on the convex portion 12 (top surface 121) can be suppressed. Therefore, the convex portion 12 and the glaze 15 disposed on the convex portion 12 (particularly its cross-sectional shape as viewed along the x direction) are different from each other on the upstream and downstream sides in the y direction (the transversal direction of the base materials 10, 10A, etc.). The sides are balanced, and it is possible to suppress variations in print quality of the thermal print head A1. In addition, the same effects as in the case of the manufacturing method shown in FIGS. 7 to 15 can be achieved.

Next, still another example of the method for manufacturing the thermal print head A1 will be described below with reference to FIGS. 21 to 26. 21 to 26 are cross-sectional views showing one step of the method for manufacturing the thermal print head A1, and correspond to the cross-section shown in FIG. 6. Note that in these figures, descriptions of steps that are the same as or similar to those described with reference to FIGS. 7 to 15 are omitted as appropriate.

In the manufacturing method shown in FIGS. 21 to 26, the arrangement of the glass paste (first glass paste 15A) is mainly different from that in the manufacturing method of the thermal print head A1 described with reference to FIGS. 7 to 15 above. It's different.

In this manufacturing method, first, as shown in FIG. 21, a predetermined mask layer 95 is formed on a portion of the main surface 11A of the prepared base material 10A. An opening 95a is formed in this mask layer 95. The opening 95a has an elongated rectangular shape that extends in the x direction when viewed in the z direction. The formation area of the opening 95a corresponds to the top surface 121 of the convex portion 12 that will be formed later.

Next, as shown in FIG. 22, a recess 12A is formed in the main surface 11A of the base material 10A. The recessed portion 12A is formed by, for example, dry etching. The recess 12A has a shape corresponding to the opening 95a of the mask layer 95, and has an elongated rectangular shape that extends in the x direction when viewed in the z direction. Thereafter, mask layer 95 is removed.

Next, as shown in FIGS. 23 to 25, a glaze 15 is formed. In this manufacturing method, first, as shown in FIG. 23, a glass paste (first glass paste 15A) is placed in the recess 12A of the base material 10A and heated. In this embodiment, the first glass paste 15A is placed by applying the glass paste using a dispenser (not shown). The first glass paste 15A is arranged in an elongated rectangular shape extending in the x direction when viewed in the z direction. In this manufacturing method, the placement area of the first glass paste 15A is defined by the recess 12A. After that, the first glass paste 15A is heated (temporary firing). As a result, first glaze 15B is formed. In this embodiment, the first glass paste 15A is adjusted so that the coefficient of thermal expansion of the first glaze 15B after firing is approximately the same as that of Si, which is the material of the base material 10. Note that the composition of the first glass paste 15A is not limited.

Next, as shown in FIG. 24, a glass paste (second glass paste 15C) is placed on the first glaze 15B. The second glass paste 15C is placed by applying the glass paste using a dispenser (not shown). The second glass paste 15C is arranged in an elongated rectangular shape extending in the x direction when viewed in the z direction. In this application, since the second glass paste 15C is placed on the first glaze 15B, the dimension in the z direction is made larger than in the case of the first application in which the first glass paste 15A is placed on the base material 10A. (for example, about 3 times as much), the second glass paste 15C can be placed. In other words, in this embodiment, the glaze 15 can be formed overwhelmingly thicker (for example, about 4 times) than when it is formed by applying the glass paste once and firing it.

Thereafter, by heating (baking) the second glass paste 15C, a second glaze 15D is formed as shown in FIG. 25. The first glaze 15B is softened by the firing, and the glaze 15 is formed by combining with the second glaze 15D formed by firing the second glass paste 15C. In this embodiment, the second glass paste 15C placed in the second application has the same composition as the first glass paste 15A placed in the first application. Therefore, the glaze 15 formed by the second heating (firing) is integrated. Note that in FIG. 25, for convenience, the boundary between the first glaze 15B and the second glaze 15D is shown by a broken line. Note that the second glass paste 15C disposed for the second time may have a different composition from the first glass paste 15A disposed for the first time. The glaze 15 has round portions 151 formed at both ends of its surface in the y direction.

As described above, the glaze 15 is formed by repeating the process of coating and heating the glass paste twice.

Next, as shown in FIG. 26, convex portions 12 are formed. The convex portions 12 are formed by anisotropically etching the base material 10A using the glaze 15 formed in the concave portions 12A of the base material 10A as a mask (anisotropic etching step). Thereby, as shown in FIG. 26, a base material 10 having a main surface 11 and a convex portion 12 is formed. The main surface 11 is a (100) plane like the main surface 11A. The convex portion 12 has a top surface 121 and a pair of inclined outer surfaces 122. The entire top surface 121 is covered with the glaze 15. The bottom surface portion of the concave portion 12A that was covered with the glaze 15 in FIG. 25 becomes the top surface 121 of the convex portion 12. Each of the pair of inclined outer surfaces 122 is a (111) plane, and is inclined with respect to the main surface 11 and the top surface 121. The process of forming the protrusion 12 corresponds to the "anisotropic etching process" of the present disclosure.

Thereafter, in the same manner as described above with reference to FIGS. 12 to 15, the insulating layer 19 is formed, the resistor film 4A is formed, the conductive film 3A is formed, and the conductive film 3A and the resistor film 4A are partially formed. Removal (heat generating part forming step) and division of the base material 10 into individual pieces are performed sequentially. Thereby, the head substrate 1 is obtained. Then, by assembling the head board 1 and the connection board 5 onto the heat dissipation member 8, mounting the driver IC 7 on the connection board 5, bonding the plurality of wires 61 and 62, and forming the protective resin 78, as shown in FIG. The thermal print head A1 shown in FIGS. 1 to 6 is manufactured.

Also in this manufacturing method, relative positional deviation in the y direction between the convex portion 12 and the glaze 15 disposed on the convex portion 12 (top surface 121) can be suppressed. Therefore, the convex portion 12 and the glaze 15 disposed on the convex portion 12 (particularly its cross-sectional shape as viewed along the x direction) are different from each other on the upstream and downstream sides in the y direction (the transversal direction of the base materials 10, 10A, etc.). The sides are balanced, and it is possible to suppress variations in print quality of the thermal print head A1. In addition, the same effects as in the case of the manufacturing method shown in FIGS. 7 to 15 can be achieved.

Further, according to the present manufacturing method, as shown in FIG. 23, the arrangement area of the first glass paste 15A is defined by the recess 12A, and the dimension of the first glass paste 15A in the y direction is the same as that of the recess 12A in the y direction. The dimensions are the same. Therefore, the dimension in the y direction of the top surface 121 of the convex portion 12 (see FIG. 25), which is covered by the lower surface of the glaze 15 that is finally formed, is derived from the dimension in the y direction of the concave portion 12A. Therefore, the dimension in the y direction (dimension W2 in FIG. 6) of the upper end portion (top surface 121) of the convex portion 12 can be accurately defined.

Although the method for manufacturing the thermal print head A1 has been described using various examples, the method for manufacturing the thermal print head according to the present disclosure is not limited to these. For example, if the required thickness (or aspect ratio) of the glaze 15 is small, in the above manufacturing method, the step of placing the second glass paste 15C and then heating (firing) it can be omitted and the glass The glaze 15 may be formed by placing and heating (baking) the paste. FIG. 27 shows a thermal print head A1' having a glaze 15 formed by one-time placement and heating of glass paste, and is a modification of the thermal print head A1 according to the first embodiment. Furthermore, if the required thickness (or aspect ratio) of the glaze 15 is large, the glaze 15 may be formed by repeating the arrangement and heating (baking) of the glass paste three or more times.

The drawings from FIG. 28 onward illustrate other embodiments of the present disclosure. In the drawings after FIG. 28, elements that are the same or similar to those in the embodiment described above are given the same reference numerals as in the embodiment described above, and explanations thereof will be omitted as appropriate.

<Second embodiment>
FIG. 28 is an enlarged sectional view of a main part showing a thermal print head according to a second embodiment of the present disclosure, and corresponds to FIG. 6. In the thermal print head A2 of this embodiment, the pair of inclined outer surfaces 122 of the convex portion 12 are each inclined in two steps, and this point is greatly different from the embodiments described above.

Each of the pair of inclined outer surfaces 122 according to this embodiment has a first inclined surface 123 and a second inclined surface 124, as shown in FIG. The first inclined surface 123 and the second inclined surface 124 are lined up in the y direction. The first inclined surface 123 and the second inclined surface 124 have different inclination angles with respect to the main surface 11. The first inclined surface 123 has an inclination angle α1 of, for example, 54.8 degrees with respect to the main surface 11. On the other hand, the second inclined surface 124 has an inclination angle α2 of, for example, 30.1 degrees with respect to the main surface 11. The first inclined surface 123 is connected to the main surface 11 and the second inclined surface 124 and is sandwiched therebetween. The second inclined surface 124 is connected to and sandwiched between the first inclined surface 123 and the top surface 121. The first inclined surface 123 is a (111) plane.

In this embodiment, the glaze 15 covers the entire top surface 121 of the convex portion 12 and at least a portion of the pair of second inclined surfaces 124. In this embodiment, the glaze 15 is formed by disposing and heating (firing) a glass paste in one step, as shown in the manufacturing method described below.

Next, an example of a method for manufacturing the thermal print head A2 will be described below with reference to FIGS. 29 to 35. 29 to 35 are cross-sectional views showing one step of the method for manufacturing the thermal print head A2, and correspond to the cross-section shown in FIG. 28.

First, as shown in FIG. 29, a predetermined mask layer 96 is formed on a portion of the main surface 11A of the prepared base material 10A. The mask layer 96 is, for example, a dry film photoresist, and is attached to the main surface 11A. By exposing and developing this mask layer 96, the exposed portion is removed and an opening 96a is formed (step of forming a dry film photoresist). The opening 96a has an elongated rectangular shape that extends in the x direction when viewed in the z direction. Mask layer 96 made of dry film photoresist is relatively thick. The thickness of the mask layer 96 is, for example, about 75 μm.

Next, glass paste (first glass paste 15A) is printed on the base material 10 by a screen printing technique. As a result, the first glass paste 15A is placed only on the exposed portion (opening 96a portion) not covered by the mask layer 96 on the base material 10 (step of placing the first glass paste).

Next, as shown in FIG. 31, the mask layer 96 is peeled off (step of peeling off the dry film photoresist). Here, the mask layer 96 is removed by, for example, peeling using an organic agent or peeling using an adhesive tape. Next, by heating (baking) the first glass paste 15A, a first glaze 15B is formed as shown in FIG. 32.

Next, as shown in FIGS. 33 and 34, the convex portions 12 are formed. The convex portions 12 are formed by performing anisotropic etching on the base material 10A using the first glaze 15B formed on the main surface 11A as a mask (anisotropic etching step). In the process of forming the convex portions 12, for example, anisotropic etching using an alkaline aqueous solution is performed. Examples of the alkaline aqueous solution include KOH and TMAH.

In this embodiment, the step of performing anisotropic etching is performed twice. As shown in FIG. 33, the first anisotropic etching forms a convex portion 12 having a top surface 121 and a pair of inclined outer surfaces 122 (first inclined surfaces 123). Here, depending on conditions such as the adhesion of the first glaze 15B to the base material 10, a portion of the base material 10 is removed below both ends of the first glaze 15B in the y direction. Then, by the second anisotropic etching, as shown in FIG. 34, a portion of the base material 10 is further removed below both ends of the first glaze 15B in the y direction. By performing anisotropic etching twice in this way, a pair of inclined outer surfaces 122 each having a first inclined surface 123 and a second inclined surface 124 are formed. As shown in FIG. 34, both ends of the first glaze 15B in the y direction overlap a pair of second inclined surfaces 124 (a pair of inclined outer surfaces 122) when viewed in the z direction.

In this embodiment, the first glaze 15B is then heated (refired) again to form the glaze 15 as shown in FIG. 35. The first glaze 15B is softened by the re-firing, and a glaze 15 having a shape that covers the top surface 121 and the pair of second inclined surfaces 124 is formed. The glaze 15 has round portions 151 formed at both ends of its surface in the y direction. The subsequent steps are similar to the method for manufacturing the thermal print head A1.

Next, the operation of this embodiment will be explained.

In manufacturing the thermal print head A2 of this embodiment, a first glaze 15B extending in the x direction (main scanning direction) is formed on the base material 10A, and then, using the first glaze 15B as a mask, a single crystal semiconductor is formed. Anisotropic etching is performed on the base material 10A. In the subsequent process, a plurality of heat generating parts 41 arranged in the x direction are formed on the glaze 15. In the step of performing anisotropic etching using the first glaze 15B as a mask, a main surface 11 facing upward in the z-direction and a convex portion 12 protruding from the main surface 11 in the z-direction are formed on the base material 10. be done. The convex portion 12 has a top surface 121 that is parallel to the main surface 11 , and the entire top surface 121 is covered with the glaze 15 .

According to this embodiment, relative positional displacement in the y direction between the convex portion 12 and the glaze 15 disposed on the convex portion 12 (top surface 121) can be suppressed. Therefore, the convex portion 12 and the glaze 15 disposed on the convex portion 12 (particularly its cross-sectional shape as viewed along the x direction) are different from each other on the upstream and downstream sides in the y direction (the transversal direction of the base materials 10, 10A, etc.). The sides are balanced, and it is possible to suppress variations in print quality of the thermal print head A2. Furthermore, since the convex portion 12 is formed by performing anisotropic etching on a single crystal semiconductor, its yz cross section is approximately uniform in the x direction (longitudinal direction of the base materials 10, 10A, etc.). Become. That is, the pressing contact state of the print medium with the heat generating portion 41 is approximately constant at various locations in the x direction. This does not change even if the manufacturing lot of the head substrate 1 is different, and is suitable for suppressing variations in printing quality.

Further, in this embodiment, a dry film photoresist is used as the mask layer 96 formed on the base material 10. The mask layer 96 having a relatively thick thickness can be formed accurately and easily. The thickness of the glaze 15 can be made sufficiently thick by disposing the glass paste (first glass paste 15A) once.

According to the present embodiment, by performing the anisotropic etching process twice on the base material 10A using the first glaze 15B as a mask, the convex portion 12 has a pair of inclined outer surfaces 122 each inclined in two steps. is formed. Specifically, each inclined outer surface 122 has a first inclined surface 123 and a second inclined surface 124 having different inclination angles with respect to the main surface 11. The inclination angle α2 of the second inclined surface 124 with respect to the main surface 11 is smaller than the inclination angle α1 of the first inclined surface 123 with respect to the main surface 11. After forming the convex portions 12, the first glaze 15B is heated again to soften the first glaze 15B and form a shape that covers all of the top surface 121 and at least a portion of the pair of second inclined surfaces 124. A glaze 15 is formed. According to such a configuration, the glaze 15 can be formed over a relatively wide range of the surface of the convex portion 12, and the heat storage effect of the glaze 15 can be improved.

In this embodiment, a case has been described in which the process of anisotropically etching the base material 10A is performed twice using the first glaze 15B as a mask, but it is also possible to perform the process of anisotropically etching only once. may be configured. By performing the anisotropic etching process once, the convex portion 12 having the top surface 121 and a pair of first inclined surfaces 123 (slanted outer surfaces 122) is formed. Thereafter, by heating the first glaze 15B again, the first glaze 15B is softened, and the glaze 15 is shaped to cover the entire top surface 121 and at least a portion of the pair of first inclined surfaces 123 (slanted outer surfaces 122). is formed.

<Third embodiment>
FIG. 36 is an enlarged sectional view of main parts showing a thermal print head according to a third embodiment of the present disclosure, and corresponds to FIG. 6. The thermal print head A3 of this embodiment differs greatly from the embodiment described above in the configuration of the convex portion 12.

In this embodiment, the convex portion 12 has a top surface 121, a pair of inclined inner surfaces 125, and a pair of inclined outer surfaces 122. The top surface 121 is parallel to the main surface 11 and is substantially flat. The top surface 121 is located away from the main surface 11 in the z direction. The top surface 121 has an elongated rectangular shape that extends in the x direction when viewed in the z direction.

A pair of inclined inner surfaces 125 sandwich the top surface 121 in the y direction. Further, the pair of inclined inner surfaces 125 are connected to the top surface 121, and as they move away from the top surface 121 in the z direction (as they move upward in the figure), they move away from each other in the y direction with respect to the top surface 121. It is sloping. Each inclined inner surface 125 is substantially flat. The inclination angle α3 of each inclined inner surface 125 with respect to the top surface 121 is, for example, 54.8 degrees. Each inclined inner surface 125 is a (111) plane.

The pair of inclined outer surfaces 122 sandwich the top surface 121 and the pair of inclined inner surfaces 125 in the y direction. Further, the pair of inclined outer surfaces 122 are connected to the main surface 11 and the inclined inner surface 125, respectively, and are sandwiched therebetween in the y direction. The pair of inclined outer surfaces 122 are inclined with respect to the main surface 11 so that as they move away from the main surface 11 in the z direction (as they move upward in the figure), they approach each other in the y direction. Each inclined outer surface 122 is substantially flat. The inclination angle α1 of each inclined outer surface 122 with respect to the main surface 11 is, for example, 54.8 degrees. Each inclined outer surface 122 is a (111) plane.

As shown in FIG. 36, in the convex portion 12, a region surrounded by a top surface 121 and a pair of inclined inner surfaces 125 sandwiching the top surface 121 has a concave shape in the z direction (downward in the figure). Glaze 15 is arranged in a region surrounded by top surface 121 and a pair of inclined inner surfaces 125. Glaze 15 covers all of top surface 121 and a pair of inclined inner surfaces 125. Furthermore, in the present embodiment, the glaze 15 protrudes in the z direction (upward in the figure) beyond the region surrounded by the top surface 121 and the pair of inclined inner surfaces 125. The glaze 15 is relatively thick. The thickness of the glaze 15 is, for example, 150 μm or more and 200 μm or less.

Next, an example of a method for manufacturing the thermal print head A3 will be described below with reference to FIGS. 37 to 44. 37 to 44 are cross-sectional views showing one step of the method for manufacturing the thermal print head A3, and correspond to the cross-section shown in FIG. 36.

First, as shown in FIG. 37, a predetermined mask layer 97 is formed on a portion of the main surface 11A of the prepared base material 10A. An opening 97a is formed in this mask layer 97. The opening 97a has an elongated rectangular shape that extends in the x direction when viewed in the z direction.

Next, as shown in FIG. 38, a recess 12A is formed in the main surface 11A of the base material 10A. The recessed portion 12A is formed by anisotropic etching. In the step of forming the recessed portion 12A, for example, anisotropic etching using an alkaline aqueous solution is performed. Examples of the alkaline aqueous solution include KOH and TMAH. The recess 12A has a shape corresponding to the opening 97a of the mask layer 97 and extends in the x direction. The recess 12A has a bottom surface 121' and a pair of inclined inner surfaces 125. A pair of inclined inner surfaces 125 sandwich the bottom surface 121' in the y direction. The bottom surface 121' is a portion that becomes the top surface 121 of the convex portion 12 through a later process. The depth (dimension in the z direction) of the recess 12A is, for example, 150 μm or more and 200 μm or less. Thereafter, mask layer 97 is removed.

Next, as shown in FIG. 39, a glaze 15 is formed. In this embodiment, glass paste (first glass paste) is placed in the recess 12A and heated. In this embodiment, the first glass paste is placed, for example, by applying the glass paste using a dispenser (not shown). Note that the glass paste may be arranged by screen printing using a screen. Next, the first glaze 15B (glaze 15) is formed by heating (baking) the first glass paste.

Next, as shown in FIG. 40, convex portions 12 are formed. The convex portions 12 are formed by performing anisotropic etching on the base material 10A using the glaze 15 as a mask (anisotropic etching step). In the process of forming the convex portions 12, for example, anisotropic etching using an alkaline aqueous solution is performed. Examples of the alkaline aqueous solution include KOH and TMAH.
Thereby, as shown in FIG. 40, a base material 10 having a main surface 11 and a convex portion 12 is formed. The main surface 11 is a (100) plane like the main surface 11A. The convex portion 12 has a top surface 121, a pair of inclined inner surfaces 125, and a pair of inclined outer surfaces 122. Here, the bottom surface 121' portion of the concave portion 12A shown in FIG. 38 becomes the top surface 121 of the convex portion 12 by subjecting the base material 10A to anisotropic etching using the glaze 15 as a mask. The main surface 11 of the base material 10 is located lower than the top surface 121 (lower in FIG. 40). The pair of inclined outer surfaces 122 sandwich the top surface 121 and the pair of inclined inner surfaces 125 in the y direction.

In this embodiment, the exposed portion of the base material 10A that is not covered with the glaze 15 is removed, and the convex portion 12 having a pair of inclined outer surfaces 122 is formed. The glaze 15 has a pair of round portions 151 formed at both ends of its surface in the y direction. Due to the pair of round parts 151, the surface of the glaze 15 is smoothly continuous over each inclined outer surface 122 of the convex part 12. The subsequent steps are similar to the method for manufacturing the thermal print head A1.

Next, the operation of this embodiment will be explained.

In manufacturing the thermal print head A3 of this embodiment, a glaze 15 extending in the x direction (main scanning direction) is formed on the base material 10A, and then, using the glaze 15 as a mask, the base material 10A, which is a single crystal semiconductor, is coated. Perform anisotropic etching. In the subsequent process, a plurality of heat generating parts 41 arranged in the x direction are formed on the glaze 15. In the step of performing anisotropic etching using the glaze 15 as a mask, the base material 10 is formed with a main surface 11 facing upward in the z-direction and a convex portion 12 protruding from the main surface 11 in the z-direction. . The convex portion 12 has a top surface 121 that is parallel to the main surface 11 , and the entire top surface 121 is covered with the glaze 15 .

According to this embodiment, relative positional displacement in the y direction between the convex portion 12 and the glaze 15 disposed on the convex portion 12 (top surface 121) can be suppressed. Therefore, the convex portion 12 and the glaze 15 disposed on the convex portion 12 (particularly its cross-sectional shape as viewed along the x direction) are different from each other on the upstream and downstream sides in the y direction (the transversal direction of the base materials 10, 10A, etc.). The sides are balanced, and it is possible to suppress variations in print quality of the thermal print head A3. Furthermore, since the convex portion 12 is formed by performing anisotropic etching on a single crystal semiconductor, its yz cross section is approximately uniform in the x direction (longitudinal direction of the base materials 10, 10A, etc.). Become. That is, the pressing contact state of the print medium with the heat generating portion 41 is approximately constant at various locations in the x direction. This does not change even if the manufacturing lot of the head substrate 1 is different, and is suitable for suppressing variations in print quality.

In this embodiment, before forming the glaze 15, a recess 12A extending in the x direction is formed in the base material 10A. The recess 12A is formed by anisotropic etching and has a bottom surface 121' and a pair of inclined inner surfaces 125 sandwiching the bottom surface 121' in the y direction. The depth (dimension in the z direction) of the recess 12A is relatively large. According to such a configuration, the glaze 15 having a predetermined shape corresponding to the recess 12A and having a sufficiently thick thickness can be formed by disposing the glass paste in the recess 12A, and the heat storage effect of the glaze 15 can be improved. It is possible to improve the

By using the thermal print head described in each of the above embodiments in a thermal printer, a thermal printer having the following advantages can be obtained. First, in the thermal print head, the convex portion 12 and the glaze 15 disposed on the convex portion 12 (especially its cross-sectional shape when viewed along the x direction) are direction), the upstream and downstream sides are balanced. This suppresses variations in print quality of the thermal print head. Therefore, a thermal printer in which variations in printing quality are suppressed can be obtained. Second, the press contact state between the heat generating part 41 of the thermal print head and the print medium is approximately constant at various locations in the x direction. Therefore, even if the manufacturing lot of the head substrate 1 is different, variations in print quality due to the thermal print head can be suppressed. Therefore, also from this point of view, it is possible to obtain a thermal printer in which variations in print quality are suppressed. Thirdly, in the thermal print head, the heat storage effect of the glaze 15 can be improved. Therefore, a thermal printer capable of printing with low power consumption can be obtained.

The thermal print head and the method of manufacturing the thermal print head according to the present disclosure are not limited to the embodiments described above. The specific configuration of each part of the thermal print head according to the present disclosure and the specific processing of each step of the method for manufacturing the thermal print head according to the present disclosure can be variously changed in design.

In the embodiment described above, the protrusions 12 made of Si are formed by etching the base material 10A after forming the glaze 15 on the base material 10A. However, the present invention is not limited to this, and after forming the convex portion 12 made of Si by etching the base material 10A, a glass paste may be placed on the top surface 121 of the convex portion 12. In this case, the glass paste is placed by discharging the glass paste onto the top surface 121 using, for example, a dispenser. Further, glass paste may be placed on the top surface 121 by screen printing. Thereafter, a glaze 15 is formed on the top surface 121 of the convex portion 12 by firing (heating) the glass paste. In these cases, a portion exposed from the glaze 15 may be formed on the top surface 121 of the convex portion 12. First, a portion of the top surface 121 of the convex portion 12 that is not covered with the glaze 15 may be formed at one end or both ends along the x direction (main scanning direction). Second, a portion of the top surface 121 of the convex portion 12 that is not covered with the glaze 15 may be formed at one end or both ends along the y direction (sub-scanning direction).

[Appendix 1]
a step of preparing a base material made of a single crystal semiconductor;
a glaze forming step of forming a glaze made of a glass material and extending in the main scanning direction on the base material;
an anisotropic etching step of performing anisotropic etching on the base material using the glaze as a mask;
a heat generating part forming step of forming a plurality of heat generating parts arranged in the main scanning direction on the glaze;
In the anisotropic etching step, a thermal etching step is performed to form, on the base material, a main surface facing one side in the thickness direction, and a convex portion that protrudes from the main surface and has a top surface covered with the glaze. How to manufacture printheads.
[Appendix 2]
The glaze forming step includes the steps of disposing a first glass paste on the base material, and forming a first glaze by heating the first glass paste. How to manufacture printheads.
[Appendix 3]
The glaze forming step is performed after the step of forming the first glaze, and includes a step of disposing a second glass paste on the first glaze, and heating the second glass paste to form the first glaze. The method for manufacturing a thermal print head according to appendix 2, including the step of forming a second glaze that is thicker than the glaze.
[Appendix 4]
The first heating temperature that is the heating temperature of the first glass paste in the step of forming the first glaze is higher than the second heating temperature that is the heating temperature of the second glass paste in the step of forming the second glaze. The method for manufacturing a thermal print head according to appendix 3, wherein the method is low.
[Appendix 5]
Further comprising a recess forming step performed before the glaze forming step, forming a recess extending along the main scanning direction in the base material,
The method for manufacturing a thermal print head according to appendix 2, wherein in the step of disposing the first glass paste, the first glass paste is disposed in the recess.
[Appendix 6]
The method for manufacturing a thermal print head according to appendix 3, wherein in the step of disposing the first glass paste and the step of disposing the second glass paste, a glass paste is applied onto the base material.
[Appendix 7]
The method for manufacturing a thermal print head according to appendix 3, wherein in the step of disposing the first glass paste and the step of disposing the second glass paste, the first glass paste and the second glass paste are disposed by screen printing. .
[Appendix 8]
The method for manufacturing a thermal print head according to appendix 7, wherein in the step of disposing the first glass paste and the step of disposing the second glass paste, printing is performed using a metal mask in which slits are formed.
[Appendix 9]
The glaze forming step is performed before the step of disposing the first glass paste, and includes the step of forming a dry film photoresist having an opening on the substrate,
The method for manufacturing a thermal print head according to appendix 2, wherein in the step of disposing the first glass paste, the first glass paste is disposed on the base material via the opening of the dry film photoresist. .
[Appendix 10]
The thermal print according to appendix 9, wherein the glaze forming step is performed between the step of disposing the first glass paste and the step of forming the first glaze, and includes the step of peeling off the dry film photoresist. Head manufacturing method.
[Appendix 11]
The convex portion has a pair of inclined outer surfaces sandwiching the top surface in the sub-scanning direction,
Both ends of the first glaze in the sub-scanning direction overlap the pair of inclined outer surfaces when viewed in the thickness direction of the base material,
The method for manufacturing a thermal print head according to appendix 9 or 10, further comprising a step of heating the first glaze again, which is performed after the anisotropic etching step.
[Appendix 12]
The recess has a bottom surface and a pair of inclined inner surfaces connected to the bottom surface and sandwiching the bottom surface in the sub-scanning direction,
The method for manufacturing a thermal print head according to appendix 5, wherein the pair of inclined inner surfaces move away from each other in the sub-scanning direction as they move away from the bottom surface in the thickness direction of the base material.
[Appendix 13]
The method for manufacturing a thermal print head according to appendix 12, wherein the recess is formed by subjecting the base material to anisotropic etching.
[Appendix 14]
14. The method of manufacturing a thermal print head according to appendix 13, wherein the bottom surface of the recess becomes the top surface of the protrusion through the anisotropic etching step performed after the glaze forming step.
[Appendix 15]
The single crystal semiconductor is made of Si,
15. The method for manufacturing a thermal print head according to any one of appendices 1 to 14, wherein the main surface is a (100) plane.
[Appendix 16]
a base material made of a single crystal semiconductor and having a main surface facing one side in the thickness direction;
a resistor layer formed on the main surface and including a plurality of heat generating parts arranged in the main scanning direction;
an insulating layer formed between the base material and the resistor layer;
a glaze formed between the base material and the plurality of heat generating parts and made of a glass material;
Equipped with
The base material has a convex portion that protrudes from the main surface and extends in the main scanning direction,
The convex portion has a top surface parallel to the main surface,
The glaze covers the top surface of the thermal print head.
[Appendix 17]
The convex portion has a pair of inclined outer surfaces connected to the main surface and sandwiching the top surface in the sub-scanning direction,
The thermal print head according to appendix 16, wherein the pair of inclined outer surfaces are inclined with respect to the main surface so that they approach each other in the sub-scanning direction as they move away from the main surface in the thickness direction of the base material. .
[Appendix 18]
The thermal print head according to appendix 17, wherein the pair of inclined outer surfaces are connected to the top surface.
[Appendix 19]
The pair of inclined outer surfaces each have a first inclined surface and a second inclined surface that are connected to each other,
The first inclined surface is connected to the main surface and is sandwiched between the main surface and the second inclined surface,
The second inclined surface is connected to the top surface and is sandwiched between the first inclined surface and the top surface,
The thermal print head according to appendix 18, wherein the angle of inclination of the second inclined surface with respect to the main surface is smaller than the angle of inclination of the first inclined surface with respect to the main surface.
[Appendix 20]
The thermal print head according to attachment 19, wherein the glaze covers at least a portion of each of the second inclined surfaces.
[Appendix 21]
The convex portion has a pair of inclined inner surfaces connected to the top surface and sandwiching the top surface in the sub-scanning direction,
The pair of inclined inner surfaces are inclined with respect to the top surface so as to move away from each other in the sub-scanning direction as they move away from the top surface in the thickness direction of the base material,
18. The thermal print head according to attachment 17, wherein the glaze is disposed in a region surrounded by the top surface and the pair of inclined inner surfaces.
[Appendix 22]
22. The thermal print head according to any one of appendices 16 to 21, wherein the glaze includes a first glaze formed on the top surface and a second glaze formed on the first glaze.
[Appendix 23]
23. The thermal print head according to any one of appendices 16 to 22, wherein the glaze covers all of the top surface.
[Appendix 24]
The thermal print head according to any one of appendices 16 to 23;
A thermal printer, comprising: a platen disposed facing the plurality of heat generating parts.

A1, A1', A2, A3: Thermal print head 1: Head substrate 10: Base material 10A: Base material 11: Principal surface 11A: Principal surface 12: Convex portion 12A: Concave portion 121: Top surface 121': Bottom surface 122: Inclined Outer surface 123 : First inclined surface 124 : Second inclined surface 125 : Inclined inner surface 15 : Glaze 15A : First glass paste 15B : First glaze 15C : Second glass paste 15D : Second glaze 151 : Round part 19 : Insulating layer 2: Protective layer 21: Pad opening 3: Electrode layer 3A: Conductive film 31: Individual electrode 311: Electrode pad portion 32: Common electrode 323: Common portion 324: Comb tooth portion 4: Resistor layer 4A: Resistor Membrane 41: Heat generating part 5: Connection board 59: Connectors 61, 62: Wire 7: Driver IC
78: Protective resin 8: Heat dissipation members 91, 93: Screens 91a, 93a: Slit 92: Spacers 95, 97: Mask layer 96: Mask layer (dry film photoresist)
95a, 96a, 97a: Opening 99: Platen roller

Claims (17)

a step of preparing a base material made of a single crystal semiconductor;
a recess forming step of forming a recess extending along the main scanning direction in the base material;
a glaze forming step of forming a glaze extending in the main scanning direction and made of a glass material on the base material;
an anisotropic etching step of performing anisotropic etching on the base material using the glaze as a mask;
a heat generating part forming step of forming a plurality of heat generating parts arranged in the main scanning direction on the glaze;
The glaze forming step includes a step of placing a first glass paste in the recess, and a step of forming a first glaze by heating the first glass paste,
In the anisotropic etching step, a thermal etching step is performed to form, on the base material, a main surface facing one side in the thickness direction, and a convex portion that protrudes from the main surface and has a top surface covered with the glaze. How to manufacture printheads. The glaze forming step is performed after the step of forming the first glaze, and includes a step of disposing a second glass paste on the first glaze, and heating the second glass paste to form the first glaze. The method of manufacturing a thermal print head according to claim 1 , further comprising the step of forming a second glaze that is thicker than the glaze. The first heating temperature that is the heating temperature of the first glass paste in the step of forming the first glaze is higher than the second heating temperature that is the heating temperature of the second glass paste in the step of forming the second glaze. The method for manufacturing a thermal print head according to claim 2 , wherein the thermal print head is low. Manufacturing the thermal print head according to claim 2 , wherein in the step of disposing the first glass paste and the step of disposing the second glass paste, the first glass paste and the second glass paste are disposed by screen printing. Method. 5. The method of manufacturing a thermal print head according to claim 4 , wherein in the step of arranging the first glass paste and the step of arranging the second glass paste, printing is performed using a metal mask in which slits are formed. a step of preparing a base material made of a single crystal semiconductor;
a glaze forming step of forming a glaze made of a glass material and extending in the main scanning direction on the base material;
an anisotropic etching step of performing anisotropic etching on the base material using the glaze as a mask;
a heat generating part forming step of forming a plurality of heat generating parts arranged in the main scanning direction on the glaze;
The glaze forming step includes forming a dry film photoresist having an opening on the base material, disposing a first glass paste on the base material, and heating the first glass paste. forming a first glaze with
In the step of disposing the first glass paste, the first glass paste is disposed on the base material through the opening of the dry film photoresist;
In the anisotropic etching step, forming on the base material a main surface facing one side in the thickness direction, and a convex portion protruding from the main surface and having a top surface covered with the glaze,
The convex portion has a pair of inclined outer surfaces sandwiching the top surface in the sub-scanning direction,
Both ends of the first glaze in the sub-scanning direction overlap the pair of inclined outer surfaces when viewed in the thickness direction of the base material,
A method for manufacturing a thermal print head , further comprising a step of heating the first glaze again after the anisotropic etching step . 7. The thermal photoresist according to claim 6 , wherein the glaze forming step is performed between the step of disposing the first glass paste and the step of forming the first glaze, and includes the step of peeling off the dry film photoresist. How to manufacture printheads. The recess has a bottom surface and a pair of inclined inner surfaces connected to the bottom surface and sandwiching the bottom surface in the sub-scanning direction,
The method for manufacturing a thermal print head according to claim 1 , wherein the pair of inclined inner surfaces move away from each other in the sub-scanning direction as they move away from the bottom surface in the thickness direction of the base material. 9. The method for manufacturing a thermal print head according to claim 8 , wherein the recess is formed by anisotropically etching the base material. 10. The method of manufacturing a thermal print head according to claim 9 , wherein the bottom surface of the recessed portion becomes the top surface of the convex portion by the anisotropic etching step performed after the glaze forming step. The single crystal semiconductor is made of Si,
11. The method for manufacturing a thermal print head according to claim 1, wherein the main surface is a ( 100 ) plane. a base material made of a single crystal semiconductor and having a main surface facing one side in the thickness direction;
a resistor layer formed on the main surface and including a plurality of heat generating parts arranged in the main scanning direction;
an insulating layer formed between the base material and the resistor layer;
a glaze formed between the base material and the plurality of heat generating parts and made of a glass material;
Equipped with
The base material has a convex portion that protrudes from the main surface and extends in the main scanning direction,
The convex portion has a top surface parallel to the main surface, and a pair of inclined outer surfaces that are connected to the main surface and the top surface and sandwich the top surface in the sub-scanning direction,
The pair of inclined outer surfaces are inclined with respect to the main surface so that they approach each other in the sub-scanning direction as they move away from the main surface in the thickness direction of the base material,
The pair of inclined outer surfaces each have a first inclined surface and a second inclined surface that are connected to each other,
The first inclined surface is connected to the main surface and is sandwiched between the main surface and the second inclined surface,
The second inclined surface is connected to the top surface and is sandwiched between the first inclined surface and the top surface,
The angle of inclination of the second inclined surface with respect to the main surface is smaller than the angle of inclination of the first inclined surface with respect to the main surface,
The glaze covers the top surface of the thermal print head. The thermal print head according to claim 12 , wherein the glaze covers at least a portion of each of the second inclined surfaces. The convex portion has a pair of inclined inner surfaces connected to the top surface and sandwiching the top surface in the sub-scanning direction,
The pair of inclined inner surfaces are inclined with respect to the top surface so as to move away from each other in the sub-scanning direction as they move away from the top surface in the thickness direction of the base material,
The thermal print head according to claim 12 , wherein the glaze is arranged in an area surrounded by the top surface and the pair of inclined inner surfaces. The thermal print head according to any one of claims 12 to 14, wherein the glaze includes a first glaze formed on the top surface and a second glaze formed on the first glaze. . 16. The thermal print head according to claim 12 , wherein the glaze covers all of the top surface. The thermal print head according to any one of claims 12 to 16 ,
A thermal printer, comprising: a platen disposed facing the plurality of heat generating parts.

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