On an element substrate having a multilayered structure in which a temperature detection element is provided in an intermediate layer of a wiring layer and a print element layer, a wiring layer and a temperature detection element formed on the first interlayer insulation film are connected by a first conductive plug which penetrates through the first interlayer insulation film. In addition, a wiring layer and a print element which are formed on the second interlayer insulation film formed on the first interlayer insulation film are connected by a second conductive plug which penetrates through the first and second interlayer insulation films. By manufacturing the element substrate by this arrangement, the thickness of an interlayer insulation film between a print element and a temperature detection element can be made thin, and the sensitivity of the temperature detection element can be improved.

A thermal print head includes a head substrate (11) having a main surface (11a) on which a convex part (12) is formed, a resistor layer (21) that is formed on the main surface (11a) and the convex part (12), a wiring layer (22) that covers the resistor layer (21) such that the resistor layer (21) is exposed at a heat generating part (20) formed at a part of the convex part (12), and a protective layer (25) that is formed on the main surface (11a) of the head substrate (11) and covers the resistor layer (21) and the wiring layer (22). The resistor layer (21) has a main resistor layer that contains tantalum, and at least one of a first sub-resistor layer that contains tantalum nitride and is stacked below the tantalum layer and a second sub-resistor layer that contains tantalum nitride and is stacked on the tantalum layer. The nitrogen content of tantalum nitride contained in the first sub-resistor layer and the second sub-resistor layer exceeds a predetermined value such that the tantalum nitride is deposited in a stable structure.

A thermal head of the present disclosure includes a substrate, a heating part, an electrode, a protection layer, and a coating layer made of a resin material. The heating part is placed on or above the substrate. The electrode is placed on or above the substrate and connected to the heating part. The protection layer is placed on or above the heating part and the electrode. The coating layer is placed on or above the electrode and the protection layer. The protection layer includes a recessed part that is opened on an upper surface and that extends along a thickness direction of the protection layer. The recessed part includes an inner wall having a plurality of recesses and projections, and the resin material is disposed inside the recessed part.

On an element substrate having a multilayered structure in which a temperature detection element is provided in an intermediate layer of a wiring layer and a print element layer, a wiring layer and a temperature detection element formed on the first interlayer insulation film are connected by a first conductive plug which penetrates through the first interlayer insulation film. In addition, a wiring layer and a print element which are formed on the second interlayer insulation film formed on the first interlayer insulation film are connected by a second conductive plug which penetrates through the first and second interlayer insulation films. By manufacturing the element substrate by this arrangement, the thickness of an interlayer insulation film between a print element and a temperature detection element can be made thin, and the sensitivity of the temperature detection element can be improved.

A thermal head includes a substrate, a glaze layer, and a reinforced conductor layer. The glaze includes a first glaze and a second glaze. The first glaze extends in a predetermined direction on the surface of the substrate. The second glaze is spaced part from the first glaze to one side in a direction perpendicular to the predetermined direction on the surface of the substrate. The reinforced conductor layer includes a lateral side part. The lateral side part extends on the surface of the substrate from the first glaze side to the second glaze side and is partially located on the second glaze. An edge part on the first glaze side in the second glaze includes a cutout portion cut out toward the one side in the direction perpendicular to the predetermined direction. The lateral side part passes through the cutout portion.

The present disclosure provides a thermal print head. The thermal print head includes a substrate, having a main surface facing one side in a thickness direction; a resistor layer, including a plurality of heat generating portions arranged in a main scanning direction and supported by the substrate; and a wiring layer, forming a power path to the plurality of heat generating portions and supported by the substrate. The substrate includes a convex portion protruding from the main surface and extending along the main scanning direction. The convex portion includes: a flat first surface on which each of the plurality of heat generating portions is disposed; and a first curved convex surface connected to the first surface.

A thermal head includes a substrate; a heat generating section disposed on the substrate; an electrode electrically connected to the heat generating section; a cover layer which covers part of the electrode; a pad electrically connected to the electrode; and a joining member electrically connected to the pad. The cover layer includes a first portion and a second portion which is smaller in thickness than the first portion. The second portion is placed on the pad. The pad has a convexity which exposes from the second portion. The joining member is connected to the convexity.

A thermal head according to the present disclosure includes: a substrate; a first electrode; a heat generating section; a second electrode; a resin layer; and a protective layer. The first electrode is located on the substrate. The heat generating section is located on the substrate. The second electrode is located on the substrate so as to be electrically connected to the heat generating section and the first electrode. The resin layer is located on the first electrode. The protective layer is located on the resin layer. Moreover, the resin layer includes a first portion inserted in the first electrode.

A thermal head includes a substrate, a heat storage layer disposed on the substrate and including a bulging portion, heating elements disposed on the bulging portion, a protective layer disposed on the heating elements, and a covering layer disposed on the protective layer. The covering layer includes a first portion disposed apart from the bulging portion, and a second portion disposed between the bulging portion and the first portion. The height of the second portion from the substrate is smaller than the height of the first portion from the substrate.

The present disclosure provides an insulating substrate. The insulating substrate includes a ceramic substrate having a main surface and a planarization layer covering the main surface. The planarization layer is a ceramic layer.