Femtosecond Laser Micromachining

Femtosecond Laser Micromachining
Author: Roberto Osellame
Publisher: Springer Science & Business Media
Total Pages: 485
Release: 2012-03-05
Genre: Science
ISBN: 364223366X

Femtosecond laser micromachining of transparent material is a powerful and versatile technology. In fact, it can be applied to several materials. It is a maskless technology that allows rapid device prototyping, has intrinsic three-dimensional capabilities and can produce both photonic and microfluidic devices. For these reasons it is ideally suited for the fabrication of complex microsystems with unprecedented functionalities. The book is mainly focused on micromachining of transparent materials which, due to the nonlinear absorption mechanism of ultrashort pulses, allows unique three-dimensional capabilities and can be exploited for the fabrication of complex microsystems with unprecedented functionalities.This book presents an overview of the state of the art of this rapidly emerging topic with contributions from leading experts in the field, ranging from principles of nonlinear material modification to fabrication techniques and applications to photonics and optofluidics.

Femtosecond Laser 3D Micromachining for Microfluidic and Optofluidic Applications

Femtosecond Laser 3D Micromachining for Microfluidic and Optofluidic Applications
Author: Koji Sugioka
Publisher: Springer Science & Business Media
Total Pages: 131
Release: 2013-09-24
Genre: Technology & Engineering
ISBN: 1447155416

Femtosecond lasers opened up new avenue in materials processing due to its unique features of ultrashort pulse width and extremely high peak intensity. One of the most important features of femtosecond laser processing is that strong absorption can be induced even by materials which are transparent to the femtosecond laser beam due to nonlinear multiphoton absorption. The multiphoton absorption allows us to perform not only surface but also three-dimensionally internal microfabrication of transparent materials such as glass. This capability makes it possible to directly fabricate three-dimensional microfluidics, micromechanics, microelectronics and microoptics embedded in the glass. Further, these microcomponents can be easily integrated in a single glass microchip by the simple procedure using the femtosecond laser. Thus, the femtosecond laser processing provides some advantages over conventional methods such as traditional semiconductor processing or soft lithography for fabrication of microfluidic, optofludic and lab-on-a-chip devices and thereby many researches on this topic are currently being carried out. This book presents a comprehensive review on the state of the art and future prospects of femtosecond laser processing for fabrication of microfluidics and optofludics including principle of femtosecond laser processing, detailed fabrication procedures of each microcomponent and practical applications to biochemical analysis.

Development of Lower Cost Imaging Systems for Laser Metal Deposition Process

Development of Lower Cost Imaging Systems for Laser Metal Deposition Process
Author: Shyam Barua
Publisher:
Total Pages: 124
Release: 2011
Genre: Image analysis
ISBN:

"Laser Metal Deposition (LMD) has been used as an additive manufacturing process in industries such as aerospace and die castings. LMD is especially useful in repair applications involving die repair. However, it is still not used widely in industry due to variations in the quality of parts. There are multiple interactions between various factors which influence the quality of deposit. There exists a need for defect detection systems to detect any changes in the deposition quality during deposition. On demand detection enables adjustment in process parameters and minimization of rework cost. Vision systems have been used extensively in the industry to observe high intensity processes such as laser welding, cutting and metal deposition processes. Due to the non contact nature of the sensor unlike thermocouples or other physical sensors, there is no degradation of the sensor. In the first part of this thesis, a low cost vision system to observe the melt pool created by a diode laser is discussed. External illumination using ultraviolet light between 390-395 nanometer wavelength along with narrow band pass filters is used to illuminate the melt pool while blocking out the process radiation. A clear view of the melt pool is obtained and melt pool size measurements are obtained during laser scanning process. In the second part of this thesis, a method of defect detection in LMD is discussed, wherein the deposited track behind the melt pool is the region of interest. A digital SLR camera is used to obtain images of the deposited track behind the melt pool wherein variation in temperature gradient on the deposited track is used to detect porosity and crack defects"--Abstract, leaf iv.

Laser-based Technologies for Sustainable Manufacturing

Laser-based Technologies for Sustainable Manufacturing
Author: Avinash Kumar
Publisher: CRC Press
Total Pages: 215
Release: 2023-07-26
Genre: Technology & Engineering
ISBN: 100090797X

This book provides scientific and technological insights on novel techniques of design and manufacturing using laser technologies. It showcases applications of laser micromachining in the biomedical industry, laser-based manufacturing processes in aerospace engineering, and high-precision laser-cutting in the home appliance sector. Features: Each chapter discusses a specific engineering problem and showcases its numerical, and experimental solution Provides scientific and technological insights on novel routes of design and manufacturing using laser technologies Synergizes exploration related to the various properties and functionalities through extensive theoretical and numerical modeling Highlights current issues, developments, and constraints in additive manufacturing Discusses applications of laser cutting machines in the manufacturing industry and laser micromachining for the biomedical industry The text discusses optical, and laser-based green manufacturing technologies and their application in diverse engineering fields including mechanical, electrical, biomedical, and computer. It further covers sustainability issues in laser-based manufacturing technologies and the development of laser-based ultra-precision manufacturing techniques. The text also discusses the use of artificial intelligence and machine learning in laser-based manufacturing techniques. It will serve as an ideal reference text for senior undergraduate, graduate students, and researchers in fields including mechanical engineering, aerospace engineering, manufacturing engineering, and production engineering.

Development of Precise Femtosecond Laser Micromachining Processes for Metals and Electrospun Nanofibers

Development of Precise Femtosecond Laser Micromachining Processes for Metals and Electrospun Nanofibers
Author: ChangKyoo Park
Publisher:
Total Pages: 147
Release: 2015
Genre:
ISBN:

Femtosecond pulse lasers have proven to be versatile for micro-scale ablation of a variety of materials with high quality machining due to minimal residual stress, heat affected zone, and melting. In addition, femtosecond laser is one of the non-cleanroom techniques that does not require masking, chemical reagents, and multiple steps. This simple and convenient micromachining technique enables machining of various materials in 3-dimensional geometry. However, some factors such as optical scattering, beam shape, and debris accumulation hinder the high quality of ablation. In this dissertation, femtosecond laser was employed for the micromachining of electrospun nanofibers and metals. Optimization of a process for the high quality femtosecond laser machining was investigated. Femtosecond laser and electrospun poly(e-caprolactone) (PCL) nanofibers mesh interaction was analyzed by optical property measurements and the optical absorption and scattering coefficients were estimated. The specific energy required for ablating a unit volume of pure PCL nanofibers and polydimethylsiloxane-poly(e-caprolactone) (PDMS-PCL) core-shell nanofibers was measured. Material inherent optical properties including the ablation threshold fluence and the incubation coefficient of PDMS and PCL were estimated. Circular grooves were fabricated on aluminum, stainless steel 316, and Stellite 6 and circular disks were successfully machined from a thick section of Stellite. The tapered cross-section was detected from the Stellite disk and the tapering was minimized by varying pulse energy during ablation process. Moreover, a novel debris removal technique based on DC-dielectrophoresis (DEP) force was used to machine the linear and circular grooves on aluminum and the ablation depth and precision were compared with the gas jet debris removal technique.

Femtosecond Laser Micromachining of Low-temperature Co-fired Ceramic and Glass Fiber Reinforced Polymer Printed Circuit Boards Materials

Femtosecond Laser Micromachining of Low-temperature Co-fired Ceramic and Glass Fiber Reinforced Polymer Printed Circuit Boards Materials
Author: Raif Farkouh
Publisher:
Total Pages: 92
Release: 2017
Genre:
ISBN:

Low-temperature co-fired ceramic (LTCC), and glass fiber reinforced polymer (GFRP) printed circuit boards (PCBs) are two materials used for the packaging of electronics. The excellent mechanical and electrical properties of LTCC, combined with the ability to embed passive components offer superior radio frequency (RF) performance and device miniaturization for high-frequency applications. Due to its unique properties, LTCC provides superior performance in applications as diverse as military radar, imaging systems, advanced automotive sensing, telecommunications, and satellites. The use of LTCC in these applications has created a demand for the micromachining of holes, channels, and cavities with specific geometries and structures. Likewise, GFRP PCBs are the backbone of the electronics industry. They work to mechanically support and electrically connect components using conductive tracks, pads and other features etched from copper sheets laminated onto GFRP substrate. Since the electronics industry has been moving toward devices with smaller size and lower cost, there has been an increasing need to drill holes in GFRP PCBs with high quality and efficiency. Some of the conventional techniques used to machine LTCC and GFRP PCBs are micro punching, mechanical milling, and electrical discharge machining. These techniques can machine some structures on LTCC and GFRP PCBs, but the drawbacks such as geometry-limitation, wear and tear of tools, high-cost, complex equipment, lack of flexibility and crack-tendency limit the application of these techniques. Femtosecond laser micromachining is a comparatively new technique that offers a solution to meet the challenging demand for drilling of LTCC and GFRP PCBs. The unique properties of ultrashort pulse width and the extremely high peak intensity allow fs laser to drill high-quality holes and to minimize thermal and mechanical damage by the term of "cold" ablation mechanism. In this project, efficient processes for femtosecond laser drilling of LTCC and GFRP PCBs for RF packaging were developed. A high drilling quality with no trace of dross, debris and reacting layer was achieved. The effects of the laser parameters, including pulse energy, scanning speed, focal position, and pitch, on the hole quality, were investigated. A laser polishing process of LTCC was also developed since the reduction of surface roughness is of practical importance for achieving low microwave loss.