Laminated Piezoelectric Resonator for Accurate Temperature Sensing

Solution Overview

Problem

Existing piezoelectric resonator units face challenges in achieving accurate temperature measurement due to limited heat conduction between the temperature detection unit and the piezoelectric resonator, leading to inadequate temperature compensation and frequency accuracy.

Innovation Solution

A piezoelectric resonator unit is designed with a laminated structure that includes a semiconductor layer on one of the principal surfaces of the piezoelectric layer, allowing measurement electrodes to accurately measure temperature through the semiconductor layer, thereby enhancing heat transfer and reducing temperature differences.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a temperature detection unit is arranged on the base member or cover member with space between it and the piezoelectric resonator, then the device structure is simplified, but heat conduction is limited and temperature measurement accuracy deteriorates

Engineering Contradiction:

Improvedevice structureVSAvoidtemperature measurement accuracy

Core Design Contradiction:

Device complexityVSMeasurement precision

Solution Approach 1:

The temperature detection unit is merged with the piezoelectric resonator by laminating the semiconductor layer directly on the piezoelectric layer, eliminating the space between them. This integration ensures excellent heat conduction and accurate temperature measurement while maintaining structural simplicity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The temperature detection unit is nested within the piezoelectric resonator structure itself, with the semiconductor layer positioned between the piezoelectric layer and the first electrode. This nested configuration allows the temperature detection function to be embedded within the resonator without adding external components.

Inventive Principle:

Principle #7Nested doll (Nesting)

2Measurement precision

If a semiconductor layer is laminated on the piezoelectric layer with measurement electrodes, then temperature measurement accuracy is improved, but device complexity increases

Engineering Contradiction:

Improvetemperature measurement accuracyVSAvoidlaminated structure

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The temperature detection unit is merged with the piezoelectric resonator by laminating the semiconductor layer directly on the piezoelectric layer, eliminating the space between them. This integration ensures excellent heat conduction and accurate temperature measurement while maintaining structural simplicity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The piezoelectric resonator structure serves multiple functions: the piezoelectric layer provides frequency generation, while the laminated semiconductor layer provides temperature detection. This multi-functionality reduces the need for separate components and simplifies the overall device structure.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Ease of manufacture

If the temperature detection unit is positioned away from the piezoelectric resonator, then manufacturing is easier, but temperature compensation accuracy deteriorates

Engineering Contradiction:

Improvemanufacturing easeVSAvoidtemperature compensation accuracy

Core Design Contradiction:

Ease of manufactureVSMeasurement precision

Solution Approach 1:

The temperature detection unit is merged with the piezoelectric resonator by laminating the semiconductor layer directly on the piezoelectric layer, eliminating the space between them. This integration ensures excellent heat conduction and accurate temperature measurement while maintaining structural simplicity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The semiconductor layer is laminated on the piezoelectric layer during the manufacturing process itself, rather than adding it as a separate post-processing step. This preliminary integration ensures optimal thermal contact and simplifies the manufacturing workflow.

Inventive Principle:

Principle #10Preliminary action

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

This configuration improves temperature compensation accuracy and reduces parasitic capacitance, resulting in a quartz crystal resonator unit that outputs a frequency clock with narrow tolerance accuracy and maintains vibration characteristics.

Implementation Method 1

a piezoelectric resonator, having a mechanical vibrating portion that converts electric vibration into mechanical vibration by using a piezoelectric effect

Methodology Applied

Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 2

heat conduction is limited due to a space existing between the temperature detection unit and the piezoelectric resonator

Methodology Applied

Scientific EffectHeat conduction: Conduction (thermal)

Data Source

PatentUS12255599B2Piezoelectric resonator unit and oscillator provided with the same

Publication Date: 2025.03.18 MURATA MFG CO LTD

AI summary

A piezoelectric resonator unit that includes a base, a cover, and a laminated structure disposed between the base and the cover. The laminated structure includes a piezoelectric resonator having a piezoelectric layer with a pair of principal surfaces facing each other, and a pair of excitation electrodes disposed on respective surfaces of the pair of principal surfaces so as to face each other with the piezoelectric layer therebetween, a semiconductor layer laminated on a side of one of the pair of principal surfaces of the piezoelectric layer, and a pair of measurement electrodes provided on the semiconductor layer. The pair of measurement electrodes measure signals based on temperature of the piezoelectric resonator through the semiconductor layer.