# US 11,309,483 B2 · Piezoelectric element and liquid ejecting head

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,309,483 B2
- Document ID: US11309483B2
- Status: Granted
- Kind: B2
- Application number: 16/285,664
- Filed: 2019-02-26
- Published: 2019-08-29
- Granted: 2022-04-19
- Earliest claimed: 2018-02-27
- Assignees: Seiko Epson Corporation
- Applicants: Seiko Epson Corporation
- Inventors: Harunobu Koike; Koichi Morozumi
- Web page: https://patentgrep.com/patent/US11309483B2

## CPC

- H10N 30/8542: {Alkali metal based oxides, e.g. lithium, sodium or potassium niobates}
- B41J 2/14233: {of film type, deformed by bending and disposed on a diaphragm}
- C04B 35/495: based on vanadium, niobium, tantalum, molybdenum or tungsten oxides or solid solutions thereof with other oxides, e.g. vanadates, niobates, tantalates, molybdates or tungstates
- H10N 30/078: by sol-gel deposition
- H10N 30/093: Forming inorganic materials
- H10N 30/2047: {Membrane type}
- H10N 30/704: {based on piezoelectric or electrostrictive films or coatings}
- H10N 30/87: Electrodes or interconnections, e.g. leads or terminals
- B41J 2002/14241: {having a cover around the piezoelectric thin film element}
- B41J 2002/14419: {Manifold}
- B41J 2202/03: Specific materials used
- C04B 2235/3201: Alkali metal oxides or oxide-forming salts thereof
- H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE

## Abstract

Provided is a piezoelectric element including a first electrode provided above a substrate, a piezoelectric layer including a plurality of crystal grains containing potassium, sodium, and niobium and provided above the first electrode, and a second electrode provided above the piezoelectric layer. An atom concentration NK1 (atm %) of potassium contained in grain boundaries of the crystal grains and an atom concentration NK2 (atm %) of potassium contained in the crystal grains satisfy a relationship of 1.0<NK1/NK2≤2.4.

## Claims

### Claim 1

A piezoelectric element comprising:
a first electrode provided above a substrate;
a piezoelectric layer including a plurality of crystal grains containing potassium, sodium, and niobium and provided above the first electrode; and
a second electrode provided above the piezoelectric layer,
wherein an atom concentration NK1 (atm %) of potassium contained in grain boundaries of the crystal grains and an atom concentration NK2 (atm %) of potassium contained in the crystal grains satisfy a relationship of 1.0<NK1/NK2≤2.4.

### Claim 2 (depends on 1)

The piezoelectric element according to claim 1, wherein an atom concentration NNa1 (atm %) of sodium contained in the grain boundaries is lower than an atom concentration NNa2 (atm %) of sodium contained in the crystal grains.

### Claim 3 (depends on 2)

The piezoelectric element according to claim 2, wherein the atom concentration NNa1 and the atom concentration NNa2 satisfy a relationship of 0.55≤NNa1/NNa2≤0.75.

### Claim 4 (depends on 1)

The piezoelectric element according to claim 1, wherein the atom concentration NK1 and the atom concentration NK2 satisfy a relationship of 1.5≤NK1/NK2≤2.0.

### Claim 5 (depends on 1)

The piezoelectric element according to claim 1,
wherein the piezoelectric layer includes a plurality of layers containing the crystal grains laminated in a film thickness direction, and
wherein an atom concentration NK3 (atm %) of potassium on the second electrode side of each of the layers containing the crystal grains is higher than an atom concentration NK4 (atm %) of potassium on the first electrode side of each of the layers containing the crystal grains.

### Claim 6 (depends on 5)

The piezoelectric element according to claim 5, wherein the atom concentration NK3 and the atom concentration NK4 satisfy a relationship of 2.0≤NK3/NK4≤4.0.

### Claim 7 (depends on 5)

The piezoelectric element according to claim 5, wherein an atom concentration (atm %) of sodium contained on the second electrode side of each of the layers containing the crystal grains is lower than an atom concentration (atm %) of sodium contained on the first electrode side of each of the layers containing the crystal grains.

### Claim 8 (depends on 1)

The piezoelectric element according to claim 1, wherein an atom concentration (atm %) of potassium at centers of the grain boundaries is higher than an atom concentration (atm %) of potassium in a region in a distance equal to or longer than 70 nm from the centers of the grain boundaries.

### Claim 9 (depends on 1)

The piezoelectric element according to claim 1, wherein an atom concentration (atm %) of sodium at centers of the grain boundaries is lower than an atom concentration (atm %) of sodium in a region in a distance equal to or longer than 70 nm from the centers of the grain boundaries.

### Claim 10 (depends on 1)

A liquid ejecting head comprising the piezoelectric element according to claim 1.

### Claim 11 (depends on 2)

A liquid ejecting head comprising the piezoelectric element according to claim 2.

### Claim 12 (depends on 3)

A liquid ejecting head comprising the piezoelectric element according to claim 3.

### Claim 13 (depends on 4)

A liquid ejecting head comprising the piezoelectric element according to claim 4.

### Claim 14 (depends on 5)

A liquid ejecting head comprising the piezoelectric element according to claim 5.

### Claim 15 (depends on 6)

A liquid ejecting head comprising the piezoelectric element according to claim 6.

### Claim 16 (depends on 7)

A liquid ejecting head comprising the piezoelectric element according to claim 7.

### Claim 17 (depends on 8)

A liquid ejecting head comprising the piezoelectric element according to claim 8.

### Claim 18 (depends on 9)

A liquid ejecting head comprising the piezoelectric element according to claim 9.