Multi-tiered Orientation Layer for Piezoelectric Actuator

Solution Overview

Problem

There is a need for a configuration that achieves stable orientation of the piezoelectric layer on a diaphragm, particularly when a non-crystalline (amorphous) diaphragm, such as silicon oxide, is used in piezoelectric devices like ink jet recording heads, as existing methods fail to ensure consistent orientation.

Innovation Solution

A piezoelectric device with a diaphragm, a piezoelectric actuator having a first electrode, a piezoelectric layer, and a second electrode, where an orientation layer is introduced between the diaphragm and the piezoelectric layer, comprising a stack of two or more tiers formed by a liquid phase method, which helps in achieving preferred orientation of the piezoelectric layer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a non-crystalline (amorphous) diaphragm is used, then manufacturing flexibility and integration are improved, but stable orientation of the piezoelectric layer cannot be achieved

Engineering Contradiction:

Core Design Contradiction:

Ease of manufactureVSManufacturing precision

Solution Approach 1:

An orientation control layer is introduced as an intermediary between the amorphous diaphragm and the piezoelectric layer. This intermediate layer provides a crystalline structure that guides and stabilizes the orientation of the piezoelectric layer, enabling stable orientation control even when the underlying diaphragm is amorphous and cannot provide orientation guidance.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Device complexity

If a single-tier orientation layer is used, then device complexity is reduced, but orientation control effectiveness is insufficient

Engineering Contradiction:

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The orientation control layer is divided into multiple tiers stacked in sequence. Each tier has a specific thickness and material composition optimized for orientation control. This segmented multi-tier structure provides enhanced orientation control capability compared to a single-tier structure, while maintaining reasonable device complexity through systematic design.

Inventive Principle:

Principle #1Segmentation

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The multi-tiered orientation layer ensures a higher degree of orientation of the piezoelectric layer, improving its displacement characteristics and efficiency with reduced interference, even with an amorphous diaphragm, leading to enhanced performance in liquid ejecting applications.

Implementation Method 1

a piezoelectric layer, i.e., a layer of a material capable of electromechanical transduction or a piezoelectric material

Methodology Applied

Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 2

an orientation layer between the diaphragm and the piezoelectric layer, the orientation layer being a stack of two or more tiers

Methodology Applied

Scientific EffectEpitaxy: Epitaxy

Data Source

PatentUS11673392B2Piezoelectric device, liquid ejecting head, liquid ejecting apparatus, and method for producing piezoelectric device

Publication Date: 2023.06.13

AI summary

A piezoelectric device includes a diaphragm, a piezoelectric actuator, and an orientation layer between the diaphragm and the piezoelectric layer. The piezoelectric actuator has a first electrode, a piezoelectric layer, and a second electrode, with the first electrode, a piezoelectric layer, and a second electrode on the diaphragm. The orientation layer is a stack of two or more tiers.