Electrostatic actuator, liquid-jet head, liquid-jet apparatus, device including electrostatic actuator, method for manufacturing liquid-jet head
OwnerMasahiro Fujii, Katsuji Arakawainventors
Life of this patent
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Abstract
An electrostatic actuator includes a silicon diaphragm, an opposing electrode opposing the diaphragm with intervention of a gap therebetween, and an insulating layer formed on a surface of the diaphragm, opposing the opposing electrode. A voltage is applied between the diaphragm and the opposing electrode. The insulating layer has a laminated structure including a dielectric layer formed of a material having a higher relative dielectric constant than silicon oxide, on the diaphragm, and a surface layer exhibiting higher reduction in surface charge density than that of the dielectric layer, formed on the dielectric layer.
Claims15
An electrostatic actuator comprising:
- a diaphragm;
- an opposing electrode opposing the diaphragm with intervention of a gap therebetween, a voltage being applied between the opposing electrode and the diaphragm;
- and
- an insulating layer formed on a surface of the diaphragm opposing the opposing electrode,
- wherein the insulating layer has a laminated structure including a dielectric layer which is formed of a material having a higher relative dielectric constant than that of silicon oxide film formed on the diaphragm, and a surface layer exhibiting higher reduction in surface charge density than that of the dielectric layer, the surface layer being
- formed on the dielectric layer.
A method for manufacturing a liquid-jet head, comprising:
- an insulating layer forming step of forming a dielectric layer of a material having a higher relative dielectric constant than silicon oxide, on a surface of a cavity board where a diaphragm is to be formed, and forming a surface layer exhibiting higher reduction in surface charge density than that of the dielectric layer, on the surface of the dielectric layer, thereby forming a laminated insulating layer on the cavity board;
- a first bonding step of bonding the cavity board having the insulating layer to an electrode board having an opposing electrode in a groove, in such a manner that a region of the cavity board where the diaphragm is to be formed opposes the opposing electrode with intervention of a space in the groove therebetween;
- a cavity board etching step of etching the cavity board bonded to the electrode board to form a liquid discharge chamber including the diaphragm;
- and
- a second bonding step of bonding a nozzle board to the surface of the cavity board, opposite the electrode board.
A method for manufacturing a liquid-jet head, comprising:
- an insulating layer forming step of forming a dielectric layer of a material having a higher relative dielectric constant than silicon oxide, on a surface of a cavity board where a diaphragm is to be formed, and forming a surface layer exhibiting higher reduction in surface charge density than that of the dielectric layer, on the surface of the dielectric layer, thereby forming a laminated insulating layer on the cavity board;
- a cavity board etching step of etching the cavity board having the insulating layer to form a liquid discharge chamber including the diaphragm;
- a first bonding step of bonding the cavity board having the liquid discharge chamber to an electrode board having an opposing electrode in a groove, in such a manner that the diaphragm opposes the opposing electrode with intervention of a space in the groove therebetween;
- and
- a second bonding step of bonding a nozzle board to the surface of the cavity board, opposite the electrode board.
Dependencies are inferred from the claim text.