Abstract: A method for manufacturing a silicon carbide semiconductor device includes preparing a silicon carbide layer including an n-type region having an n conductivity type and a p-type region having a p conductivity type, forming a material layer containing titanium, aluminum, and silicon on the n-type region and the p-type region, and forming an electrode layer in contact with the n-type region and the p-type region by heating the material layer. In forming a material layer, composition of the material layer is determined such that a point (x, y, z) (x, y, and z each being a numeric value greater than 0) representing a composition ratio among titanium, aluminum, and silicon is included in a first triangular pyramidal region having four points of the origin (0, 0, 0), a point (1, 2, 2), a point (2, 1, 2) and a point (2, 2, 1) as vertices.

Abstract: When cleaning is performed to remove kogation, which is deposited on a heat acting portion, by causing an electrochemical reaction through application of a voltage between an upper electrode and an opposing electrode, a wiring located at a periphery of the opposing electrode occludes hydrogen generated during the cleaning, thereby causing hydrogen embrittlement. A unit configured to heat the wiring connected to the opposing electrode is provided, and is driven during the cleaning or after the cleaning, to thereby force hydrogen out of the wiring. Thus, the hydrogen embrittlement of the wiring is suppressed.

Abstract: A liquid discharge head has a chamber wall member forming a liquid chamber and a discharge head substrate containing a laminate of a base substrate having a surface for an element generating energy for discharging liquid. A first and second layer is formed contacting the wall. The second layer has adhesiveness with the chamber wall member higher than adhesiveness of the first layer, forming the liquid chamber with the chamber wall member. The first layer has a portion exposed from the second layer as viewed from a first direction orthogonal to the surface and contacting the chamber wail member at a position distant from the liquid chamber in a second direction orthogonal to the inner surface of the wall relative to a portion where the wall and second layer contact, and the length in the second direction of the portion of the first layer is 0.3 ?m or more.

Abstract: A method of cleaning a liquid discharge head, which includes a heat generating resistor that generates thermal energy for discharging a liquid and a covering portion covering the heat generating resistor, includes alternately performing a first voltage application process and a second voltage application process multiple times, and reducing energy applied in the second voltage application process. The first voltage application process includes applying voltage between the covering portion and an electrode through the liquid to dissolve the covering portion in the liquid. The second voltage application process includes reversing relative polarities of the covering portion and the electrode in the first voltage application process and applying voltage between the covering portion and the electrode. Energy applied in the second voltage application process is reduced such that the energy applied is less than energy applied in the first voltage application process of an immediately preceding time.

Abstract: A method of cleaning a liquid discharge head having a substrate provided with a supply port, a heat-generating resistor covered with a covering layer, a liquid chamber forming member configured to form a liquid chamber, and at least one electrode and being configured to discharge liquid supplied to the liquid chamber from the supply port by causing the heat-generating resistor to generate heat, includes applying a voltage to the covering layer and the electrode to cause an electrochemical reaction between the covering layer and the liquid and dissolve the covering layer into the liquid to remove kogations accumulated on the covering layer, in which the covering layer and the electrode to which the voltage is to be applied are not provided in the same liquid chamber having the same cross-sectional area in a direction from the covering layer toward the electrode.

Abstract: A liquid discharge head has a chamber wall member forming a liquid chamber and a discharge head substrate containing a laminate of a base substrate having a surface for an element generating energy for discharging liquid. A first and second layer is formed contacting the wall. The second layer has adhesiveness with the chamber wall member higher than adhesiveness of the first layer, forming the liquid chamber with the chamber wall member. The first layer has a portion exposed from the second layer as viewed from a first direction orthogonal to the surface and contacting the chamber wail member at a position distant from the liquid chamber in a second direction orthogonal to the inner surface of the wall relative to a portion where the wall and second layer contact, and the length in the second direction of the portion of the first layer is 0.3 ?m or more.

Abstract: Cleaning under appropriate cleaning conditions is performed by disposing an electrode pair for measuring conductivity in the same liquid chamber as that of a material layer (i.e., an upper electrode) of a surface of a thermal action portion to be eluted, and measuring conductivity of a liquid using the electrode pair before kogation is removed.

Abstract: When cleaning is performed to remove kogation, which is deposited on a heat acting portion, by causing an electrochemical reaction through application of a voltage between an upper electrode and an opposing electrode, a wiring located at a periphery of the opposing electrode occludes hydrogen generated during the cleaning, thereby causing hydrogen embrittlement. A unit configured to heat the wiring connected to the opposing electrode is provided, and is driven during the cleaning or after the cleaning, to thereby force hydrogen out of the wiring. Thus, the hydrogen embrittlement of the wiring is suppressed.

Abstract: In a method of manufacturing a liquid discharging head which includes a flow path forming member which has a discharge port for discharging a liquid and a liquid flow path communicating with the discharge port, and a base body having a liquid supply port which supplies the liquid flow path with the liquid, the method includes (1) forming a mold of the liquid flow path and a foundation member formed of a porous inorganic material over the base body, (2) applying an organic resin over the base body so as to cover the mold and the foundation member to form the flow path forming member, (3) forming the discharge port in the flow path forming member to form the liquid supply port in the base body, and (4) removing the mold to form the liquid flow path.

Abstract: A method for cleaning a liquid ejection head which includes applying a voltage to a coating layer of the liquid ejection head to cause the coating layer to be eluted in a liquid so that kogation deposited on a coating layer is removed. When removing kogation deposited on the coating layer, temperatures of the liquids in the liquid chambers are selectively changed among a plurality of liquid chambers.

Abstract: A method for cleaning a liquid ejection head which includes applying a voltage to a coating layer of the liquid ejection head to cause the coating layer to be eluted in a liquid so that kogation deposited on a coating layer is removed. When removing kogation deposited on the coating layer, temperatures of the liquids in the liquid chambers are selectively changed among a plurality of liquid chambers.

Abstract: A method of cleaning a liquid discharge head having a substrate provided with a supply port, a heat-generating resistor covered with a covering layer, a liquid chamber forming member configured to form a liquid chamber, and at least one electrode and being configured to discharge liquid supplied to the liquid chamber from the supply port by causing the heat-generating resistor to generate heat, includes applying a voltage to the covering layer and the electrode to cause an electrochemical reaction between the covering layer and the liquid and dissolve the covering layer into the liquid to remove kogations accumulated on the covering layer, in which the covering layer and the electrode to which the voltage is to be applied are not provided in the same liquid chamber having the same cross-sectional area in a direction from the covering layer toward the electrode.

Abstract: Cleaning under appropriate cleaning conditions is performed by disposing an electrode pair for measuring conductivity in the same liquid chamber as that of a material layer (i.e., an upper electrode) of a surface of a thermal action portion to be eluted, and measuring conductivity of a liquid using the electrode pair before kogation is removed.

Abstract: A recording element substrate includes a substrate; an insulating layer disposed on the substrate; a plurality of heating portions which are arranged on the insulating layer and which produce thermal energy used to eject a liquid; and a plurality of heat conduction members, each being located between adjacent heating portions with respect to an arrangement direction of the heating portions, the heat conduction members being located between the substrate side principal surface of the insulating layer and the heating portion side principal surface of the insulating layer and having higher thermal conductivity than the insulating layer. The heat conduction members are in contact with a heat conduction layer which has higher thermal conductivity than the insulating layer.

Abstract: A print head includes upper protective members located at positions corresponding to heat generating resistor elements to protect the heat generating resistor elements, and further, a part of the protective member can be eluted into ink when a current flows inside in a state in which the ink is stored in the pressure chambers. The print head includes a drive element and a logic circuit capable of allowing a current to independently flow in each of the upper protective layers so as to elute a part of the upper protective layer, in which the current flows, into the ink.

Abstract: A liquid discharge head substrate includes a base; a pair of wiring lines; a heat-generating resistive layer, which is in contact with the wiring lines, and which has a portion corresponding to a space between the wiring lines, the portion forming an electrothermal transducer; an insulating layer which covers the heat-generating resistive layer and the wiring lines and which contains Si; a protective layer which covers at least one region of the insulating layer which contains Ir; and an intermediate layer which is placed between the insulating layer and the protective layer. The intermediate layer contains a material represented by the formula TaxSiyNz, where x is 5 atomic percent to 80 atomic percent, y is 3 atomic percent to 60 atomic percent, z is 10 atomic percent to 60 atomic percent.

Abstract: A substrate for a liquid discharge head includes an upper protection film that covers at least a region corresponding to each of thermal energy generation elements. The upper protection film and at least one of the upper protection films adjacent to the upper protection film within a liquid chamber are respectively connected to different external electrodes, and a voltage can be applied therebetween via the different external electrodes.

Abstract: A print head includes upper protective members located at positions corresponding to heat generating resistor elements to protect the heat generating resistor elements, and further, a part of the protective member being eluted to ink when a current flows inside in a state in which the ink is reserved in the pressure chambers. The print head includes a drive element and a logic circuit capable of allowing a current to independently flow in each of the upper protective layers so as to elute a part of the upper protective layer, in which the current flows, to the ink.