scholarly journals Laser Micromachining of Lithium Niobate-Based Resonant Sensors towards Medical Devices Applications

Sensors ◽  
2020 ◽  
Vol 20 (8) ◽  
pp. 2206 ◽  
Author(s):  
Zeyad Yousif Abdoon Al-Shibaany ◽  
Pavel Penchev ◽  
John Hedley ◽  
Stefan Dimov
Keyword(s):  
Surface Roughness ◽  
Lithium Niobate ◽  
Medical Devices ◽  
Laser Micromachining ◽  
Q Factor ◽  
Optical Surface ◽  
Good Match ◽  
Resonant Sensors ◽  
Working Environments ◽  
Quality Factor Q

This paper presents a micromachining process for lithium niobate (LiNbO3) material for the rapid prototyping of a resonant sensor design for medical devices applications. Laser micromachining was used to fabricate samples of lithium niobate material. A qualitative visual check of the surface was performed using scanning electron microscopy. The surface roughness was quantitatively investigated using an optical surface profiler. A surface roughness of 0.526 μm was achieved by laser micromachining. The performance of the laser-micromachined sensor has been examined in different working environments and different modes of operation. The sensor exhibits a Quality-factor (Q-factor) of 646 in a vacuum; and a Q-factor of 222 in air. The good match between the modelling and experimental results shows that the laser-micromachined sensor has a high potential to be used as a resonance biosensor.

scholarly journals INVESTIGATION ON EFFECT OF SURFACE ROUGHNESS PATTERN TO DYNAMIC PERFORMANCE OF MEMS RESONATORS IN VARIOUS TYPES OF GASES AND GAS RAREFACTION

2021 ◽  
Vol 59 (5) ◽  
Author(s):  
Nguyen Chi Cuong ◽  
Lam Minh Thinh ◽  
Phan Minh Truong ◽  
Trinh Xuan Thang ◽  
Ngo Vo Ke Thanh ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Effective Viscosity ◽  
Dynamic Performance ◽  
Squeeze Film ◽  
Molecular Gas ◽  
Q Factor ◽  
Squeeze Film Damping ◽  
Mems Resonators ◽  
Quality Factor Q ◽  
Effect Of Surface

The average modified molecular gas lubrication (MMGL) equation, which is modified with pressure flow factors and effective viscosity, is utilized to analyze the squeeze film damping (SFD) on micro-beam resonators considering effect of surface roughness pattern in various types of gases and gas rarefaction. Then, effect of surface roughness pattern (film thickness ratio and Peklenik number) is discussed on the quality factor (Q-factor) of micro-beam resonators in various types of gases and gas rarefaction. Thus, effect of surface roughness pattern is significantly reduced as effective viscosity of gas decreases in higher mode of resonator and higher gas rarefaction.

scholarly journals Experimental Study on Variation of Surface Roughness and Q Factors of Fused Silica Cylindrical Resonators with Different Grinding Speeds

Micromachines ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1052
Author(s):  
Libin Zeng ◽  
Yunfeng Tao ◽  
Yao Pan ◽  
Jianping Liu ◽  
Kaiyong Yang ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Low Cost ◽  
Fused Silica ◽  
Q Factor ◽  
Cylindrical Resonator ◽  
Axisymmetric Shell ◽  
Measurement Results ◽  
Q Factors ◽  
Cylindrical Resonators ◽  
Quality Factor Q

For the axisymmetric shell resonator gyroscopes, the quality factor (Q factor) of the resonator is one of the core parameters limiting their performances. Surface loss is one of the dominating losses, which is related to the subsurface damage (SSD) that is influenced by the grinding parameters. This paper experimentally studies the surface roughness and Q factor variation of six resonators ground by three different grinding speeds. The results suggest that the removal of the SSD cannot improve the Q factor continuously, and the variation of surface roughness is not the dominant reason to affect the Q factor. The measurement results indicate that an appropriate increase in the grinding speed can significantly improve the surface quality and Q factor. This study also demonstrates that a 20 million Q factor for fused silica cylindrical resonators is achievable using appropriate manufacturing processes combined with post-processing etching, which offers possibilities for developing high-precision and low-cost cylindrical resonator gyroscopes.

scholarly journals Lithium niobate microring with ultra-high Q factor above 108

2022 ◽  
Vol 20 (1) ◽  
pp. 011902
Author(s):  
Renhong Gao ◽  
Ni Yao ◽  
Jianglin Guan ◽  
Li Deng ◽  
Jintian Lin ◽  
...  
Keyword(s):  
Lithium Niobate ◽  
Q Factor ◽  
High Q

Evaluation of DPI Change Impact on Laser Machined Surface Quality

2014 ◽  
Vol 474 ◽  
pp. 369-374
Author(s):  
Jana Knedlova ◽  
Libuše Sýkorová ◽  
Vladimír Pata ◽  
Martina Malachová
Keyword(s):  
Surface Roughness ◽  
Surface Quality ◽  
Laser Micromachining ◽  
Technological Parameters ◽  
Machined Surface ◽  
Machined Surface Quality ◽  
Machined Surface Roughness ◽  
Change Impact

The article focuses on the field of PMMA laser micromachining at change of the technological parameters. The aim was to evaluate machined surface roughness at different setting of DPI definition (number of dots paths on square inch). Commercial CO2laser Mercury L-30 by firm LaserPro, USA was used for experimental machining. Ray of laser could be focused on mark diameter d=185 mm.

scholarly journals Multiscale three-dimensional surface reconstruction and surface roughness of porcine left anterior descending coronary arteries

2019 ◽  
Vol 6 (9) ◽  
pp. 190915 ◽  
Author(s):  
Hanna E. Burton ◽  
Rachael Cullinan ◽  
Kyle Jiang ◽  
Daniel M. Espino
Keyword(s):  
Surface Roughness ◽  
Coronary Arteries ◽  
Medical Devices ◽  
Ex Vivo ◽  
Three Dimensional ◽  
Force Microscopy ◽  
Optical Scanning ◽  
Atomic Force ◽  
Reconstructed Surface ◽  
Dimensional Surface

The aim of this study was to investigate the multiscale surface roughness characteristics of coronary arteries, to aid in the development of novel biomaterials and bioinspired medical devices. Porcine left anterior descending coronary arteries were dissected ex vivo , and specimens were chemically fixed and dehydrated for testing. Surface roughness was calculated from three-dimensional reconstructed surface images obtained by optical, scanning electron and atomic force microscopy, ranging in magnification from 10× to 5500×. Circumferential surface roughness decreased with magnification, and microscopy type was found to influence surface roughness values. Longitudinal surface roughness was not affected by magnification or microscopy types within the parameters of this study. This study found that coronary arteries exhibit multiscale characteristics. It also highlights the importance of ensuring consistent microscopy parameters to provide comparable surface roughness values.

scholarly journals A Study on the Trimming Effects on the Quality Factor of Micro-Shell Resonators Vibrating in Wineglass Modes

Micromachines ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 695
Author(s):  
Lu ◽  
Xi ◽  
Xiao ◽  
Shi ◽  
Zhuo ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Quality Factor ◽  
Second Harmonic ◽  
Great Influence ◽  
Fem Simulation ◽  
Q Factor ◽  
Thermoelastic Damping ◽  
Frequency Trimming ◽  
Quality Factor Q ◽  
Anchor Loss

Frequency trimming based on mass and stiffness modification is an important post-fabrication process for micro-shell resonators (MSRs). However, the trimming effects on the quality factor are seldom studied, although they may have great influence on the performance of the resonator. This paper presents a study on the quality factor (Q-factor) variation of trimmed micro-shell resonators (MSR). Thermoelastic damping (QTED) and anchor loss (Qanchor) are found to be the dominant energy loss mechanisms resulting in the reduction of the overall Q-factor, according to finite element method (FEM). The effects of different trimming methods on QTED and Qanchor are studied here, respectively. It is found that trimming grooves ablated in the rim of the resonator can cause a ~1–10% reduction of QTED, and the length of trimming groove is positively related to the reduction of QTED. The reduction of QTED caused by the mass adding process is mainly related to the thermal expansion coefficient and density of the additive and contact area between the resonator and additive masses. Besides, the first and second harmonic errors caused by asymmetrical trimming can cause a 10–90% reduction of Qanchor. Finally, trimming experiments were conducted on different resonators and the results were compared with FEM simulation. The work presented in this paper could help to optimize the trimming process of MSRs.

Sign in / Sign up

Export Citation Format

Share Document