Multi-Arm Piezoelectric Resonator Structure for Stable DLD
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current resonant devices using MEMS technology face challenges in achieving stable drive level dependency (DLD), with existing designs prone to bending displacement and instability.
Innovation Solution
A resonator design featuring three or more vibrating arms with a base, where two outer arms and one or more inner arms vibrate in the same phase, with the outer arms being greater in mass, and incorporating a protective film and adjusting films to enhance vibration characteristics and resonant frequency adjustment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the base portion length is set to less than the width to enable easy bending displacement, then DLD is improved, but holding stability deteriorates
Solution Approach 1:
The resonator is divided into multiple vibrating arms (three or more arms) that are segmented and arranged around the base. Each arm can be independently designed with specific mass characteristics, allowing the outer arms to have greater mass than inner arms. This segmentation enables differential mass distribution that improves DLD while maintaining overall structural stability through the collective arrangement of multiple arms.
Solution Approach 2:
The invention introduces asymmetric mass distribution among the vibrating arms by making the outer arms greater in mass than the inner arms. This asymmetric configuration creates a specific vibration pattern where the mass difference generates counteracting forces that improve DLD characteristics while the symmetric arrangement of multiple arms maintains holding stability.
2Reliability
If multiple vibrating arms are used to improve vibration characteristics, then DLD is enhanced, but device complexity increases
Solution Approach 1:
Multiple vibrating arms are merged into a single integrated resonator structure that shares a common base and operates in a coordinated manner. The arms are arranged symmetrically and can be manufactured using the same process, combining multiple functional elements into a unified structure that achieves improved DLD without proportionally increasing device complexity.
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 design improves drive level dependency (DLD) by increasing the amplitude of vibrations and stabilizing the resonant frequency, leading to enhanced vibration characteristics and reduced frequency variations among resonant devices.
Implementation Method 1
a piezoelectric film provided between the first electrode and the second electrode and having a top surface facing the first electrode. Moreover, the piezoelectric film is configured to vibrate in a predetermined vibration mode when a voltage is applied between the first and second electrodes
Data Source
AI summary
A resonator is provided that includes a base, and three or more vibrating arms each including a first and second electrodes and a piezoelectric film disposed therebetween and having a top surface facing the first electrode. The piezoelectric film vibrates in a predetermined vibration mode when a voltage is applied between the first and second electrodes. Moreover, the three or more vibrating arms include two first arms each located on an outermost side in a direction in which the three or more vibrating arms are arranged and that vibrate in a same phase, and one or more second arms disposed between the two first arms. Each first arm is greater in mass than each second arm.