Laser micro-machining solutions
Workshop of PhotonicsÂŽ is all about laser micromachining.
1. Services in Femtosecond Laser Micromachining. . . 4
We develop instruments and solutions for laser micromachining tasks. From feasibility studies to customized optical modules and from electronics devices to laser machines.
1.1. Feasibility Study on Laser Micromachining. .
Our services are targeted both to industry and to academic customers. Our key competence: Feasibility studies on femtosecond laser micromachining Development of custom femtosecond laser systems and optical modules Laser system automation software Our growth is fueled by culture of open innovations and partnership with the local laser sector companies and worldwide partners. Workshop of Photonics is constantly involved in projects connecting scientific inventions with the industry needs.
1.2. Laser Process Development. .
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1.3. Custom Laser System Development. 2. Products.
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2.1. Laser Systems for Laboratories.. 2.2. Industrial Laser Machines. .
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2.3. Software for Laser Micromachining â€“ SCA . 2.4. Special Optics . .
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2.5. Beam Shaping Unit. . 2.6. MoTex. .
For more information please visit www.wophotonics.com
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2.7. Sample Holder. .
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3. Laser Micromachining Case Studies.
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3.1. Glass/Sapphire Cutting. . 3.2. Ceramics Scribing. .
3.3. Through Glass Via (TGV) Drilling.. 3.4. Other.
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3.5. Multiphoton polymerization. Partners.
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Participation in Exhibitions. .
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1. Feasibilty study 2. Laser process development (laboratory prototype)
Small scale production
3. Design of a system/module Custom laser systems for science
Laser Machines for Industry*
Warranty & support * In partnership with manufacturing machinery producers
1.1. Feasibility Study on Laser Micromachining Technology
Need to fabricate micron scale structures on the surface or in the bulk? Already tried and felt disappointed with other technologies? Our laboratories, equipped with ultra-short pulse lasers (from below 300 femtoseconds), are place where machining perfection can be achieved. Our researchers will test your materials to achieve desired fabrication mode and consult on implementation of it in mass production. Our working experience covers great variety of materials and our original micromachining software SCA allows achieving the desired results fast.
Results of a feasibility study: Principle answer if laser can be used to achieve desired results Laser parameters, at which the result is achieved (optional)
Not only different laser parameters have to be tested but also various beam shaping and focusing solutions. A typical approach for comprehensive process development contains following steps: testing of different wavelengths in order to explore light-material interaction testing of different focusing optics selecting and testing most suitable positioning solution determining, whatâ€™s required for repeatability and required speed of process optimizing software functionality for convenient process control You are welcome to contact us with specific micromachining tasks. We are committed to develop a micromachining process for you. If a task is more demanding, we are ready to involve our academic partners in search of a solution.
Services in Femtosecond Micromachining
The first step is usually a feasibility study, which indicates whether ultra-short pulsed lasers are capable to perform the task. If it is a â€œyesâ€?, then the customer decides how far to go down the steps of cooperation with Workshop of Photonics:
Most of laser micromachining applications are not as straightforward as for example marking. Most of them require development that takes weeks and even months.
Cooperation with our customers usually starts with the need to perform a specific micromachining task. The complexity of the task may depend on the material, type of fabrication, speed of processing and other requirements.
1.2. Laser Process Development
For examples of our work please see case studies in section x
1.3. Custom Laser System Development Most of applications have specific requirements. Based on a specific laser process developed in our laboratories we will design a laser machine or its optical unit to perform that process, including: Mechanical and optical design Optimum laser source selection Sample positioning system Beam delivery and scanning unit Laser power and polarization control Software for system control Machine vision Sample holders and special mechanics Other devices
Services in Femtosecond Micromachining
1. Services in Femtosecond Laser Micromachining
Our product range includes: Laser micromachining systems for laboratory Industrial laser machines Software to control laser micromachining process Optomechanical units for laser micromachining Optics based on our micromachining technologies
2.1. Laser Systems for Laboratories Every laboratory has specific applications and every scientist has its own approach. Workshop of Photonics develops customized laser systems for your laboratory, so you get what YOU need and ONLY what you need.
Based on your requirements and our partners’ and our own know-how in laser micromachining we will select appropriate configuration of the system: Laser source Sample positioning system Beam delivery and scanning unit Laser power and polarization control Software for system control Machine vision Sample holders and special mechanics Dust suction unit Other devices
Features: Modular design Best in the market laser sources Efficient beam delivery and power control Highest quality optical components Innovative positioning method developed by WOP engineers High accuracy positioning stages Additional non-stadard equipment can be integrated on request Specifications for a femtosecond laser based system: Pulse duration (<200 fs – 10 ps) Repetition rate (1 Hz – 1 MHz) Average power (up to 15W) Pulse energy: up to 2 mJ Wavelengths (1030, 515, 343, 258, 206 nm) Positioning accuracy: 300 nm Travel range: customer selected
However, for our customers we provide not only laser micromachining technologies, but also a full solution that is based on the technologies we have developed and our experience in creating laser micromachining applications.
Femtosecond laser micromachining system for scientific laboratories. Equipped with nanometer accuracy and resolution linear positioning stages, high performance galvanometer scanners and versatile micromachining software SCA, FemtoLAB becomes an entire laser laboratory on an optical table.
Applications: surface micro and nanostructuring, ablation, engraving, drilling, laser lithography and multiphoton polymerization, refractive index modification inside bulk of material, selective layer removal, your task.
Laser micromachining is our core competence, therefore no surprise that most of our time is dedicated to developing specific laser applications and technologies.
We will provide a cost-effective solution for your laboratory. A proven flexibility of FemtoLAB concept will allow you to further expand and upgrade your system when new requirements arise or budget becomes available.
Instead of powerfull laser, laser oscillator can be used and for rapid fabrication we recommend to have synchronized movement of scanner and positioning stages.
Features: Very high precision in short movement range Fast prototyping Machine vision solution for samples recognition Design of whole laboratory Market available photoresists
System Features: XYZ high accuracy sample positioning Beam delivery and shaping for selected wavelengths Control of entire system through single-window software Easily extendable, custom design 1 year warranty Applications Optional features: (*depends on end user laser): Galvanometer scanners Surface micro- and nano-structuring Safety enclosure Selective ablation External safety/modulation shutter Micro-drilling Autofocus system 3D direct laser writing Spatial light modulator Refractive index modification Polarization rotator Dicing and cutting Polarization converter (circular, ra Multiphoton polymerization (mPP) dial or azimuth) Your device integration 8
Knowing your application of laser micromachining and process needed to implement, Workshop of Photonics will develop a specific task optimized laser machine or its optical module. System configuration will be selected to assure quality, speed and reliability of execution of your task. In order to automate the fabrication process, a custom adaptation of our laser micromachining software SCA engineer can be designed (see page 10). This will not only speed up the fabrication process, but will also reduce participation of an operator to the very minimum. On the other hand, high-level users will have a special interface to configure the process or add new tasks.
FemtoLAB-KIT FemtoLAB kit is a unique femtosecond micromachining system which can be installed next to your femtosecond laser source. Depending on your laser specifications this system can become a universal tool for micromachining of different materials. Machine vision and user friendly software allows you to perform various micromachining tasks easily.
System layout and design is similar to standard FemtoLAB.
Needs of industrial customers are rather different from those of an academic laboratory: speed, repeatability and efficiency are in focus. Tee whole system has to be built around process. Therefore our laser solution usually is a part of a bigger manufacturing machine or production line. Usually it is built by specialized integrators or producers of manufacturing machinery.
FemtoFAB FemtoFAB is a turnkey femtosecond laser machine for industrial use. Configuration is selected and carefully tuned according to a specific laser micromachining application, including laser cutting, laser scribing, laser drilling and 3D laser milling with any desirable material (with >2,4 GW peak power). System is protected by Class 1 equivalent laser safety enclosure and is controlled through a single SCA engineer software window. Features: High fabrication speed â€“ up to 300 mm/s Fabrication of difficult objects with submicron resolution Minimal heat affected zone in femtosecond micromachining mode Aerotech based precise object positioning with submicron accuracy Precise laser beam control in space using high-performance galvanometer scanners Pulse number control (single to 1 MHz) Synchronization of laser pulses with moving object in space and time domains Original software interface for control of all integrated hardware devices Specifications: Task optimized, available range is similar to FemtoLAB (see page 7)
FemtoLAB-MPP workstation is application optimized laser system. Itâ€™s main purpose is multiphoton polymerization (MPP). For more information about Multiphoton polymerization go to Multiphoton Polymerization section in Case Studies.
2.2. Industrial Laser Machines
Applications: Ceramics scribing, glass cutting, saphhire cutting, TGV drilling, solar cell manufacturing, birefringent pattern fabrication, etc. 9
Dedicated for fabrication recipe preparation Free of charge Complete functionality for recipe preparation Does not connect to hardware to control it
Features of the software: Direct control of hardware starting with laser, positioning stages, galvanometric scanners and going to power attenuators and power meters, polarization rotators, machine vision, special I/O and other peripheral devices. DXF, PLT, STL, BMP file import Import of data from TXT or XML files Digital and analog I/O control Fabrication preview window Camera view calibrated with fabrication preview Machine vision (MV) module for sample detection
It makes fabrication tasks easy to describe, fine-tune and repeat. Key benefits of the software: The software eliminates the need to work with G-code completely WYSIWYG interface Convenience in entering algorithms and mathematical commands Fast and easy to correct, fine-tune and then repeat machining task Directly a wide range of equipment Customizable to fit special requirement of scientific or industrial applications
OEM version for system integrators Adapted for specific machine and specific task Special task optimized user interface Adapted to work together with other software packages
SCA software provides speed, flexibility and visibility to laser micromachining operators.
2.3. Software for Laser Micromachining â€“ SCA
Versions of the software:
Dedicated to have control of various micromachining applications and flexible systems Complete functionality Control of virtually unlimited number of positioning axis Machining rich in functions and options Live sample view through camera Complex machining tasks 10
Fig. 2.3.1. Cross-hatched shape prepared for 2.5D fabrication
Dedicated to control basic micromachining systems Control of 2 positioning axis / galvoscanners Live sample view through camera
Fig. 2.3.2. Machine vision automatically recognizes glass substrate and positions fabrication trajectories in the center of it.
SCA Competition comparison
Functionality Direct control of laser parameters Laser power control using attenuator Aero Basic code No need to work on G-code Positioning can be described using simple commands (line, circle, arc, text, dxf...) PSO (only with Aerotech stages, not SSaM) CAD, STL, DXF sketching Drag and drop Aerotech stages support Machine vision (with fabrication lines superpositioned on the sample view) Importing bitmap files (RTC4 card and Aerotech stages) Large complex 3D STL structures Spot and ablation depth compensation and hatching 2D visualization 3D visualization Autofocus with ccd camera Laser power monitoring (using specific power meters) Possibility for an industrial interface Laser power calibration table using attenuators and power meters Direct control of Aerotech stages (no need to upload code to the controller) Sample tilting compensation Laser position tracking Estimated fabrication duration New functions can be included to meet client specific requirements CNC stages Galvo scanner support (through SSaM) Galvo scanner support (through RTC4) Sample tilting detection using autofocus
SCA 2.6 Student SCA 2.6 Professor SCA 2.6 Professor MV Control of XY galvo scanner or stage motion Up to 16 axis support. Aerotech linear and rotary stages. SSaM, RTC4, RTC5 galvo scanners Rotary and additional other linear stages support Sinchronous motion of 5axis Stepper motor controller from Altechna support for linear and Rotary axes control. Attenuator control Direct laser control (PHAROS and IPG)(allows to change laser parameters in the Fabrication algorithm) Power meter support Text fabrication Text fonts support DXF file import PLT file import Bitmap file import STL file import for 3D applications. Allows to specify and modify one slice-layer of 3D model Tool for stent cutting Dashed line mode with Aerotech stages without stopping between dashes. (Allows fabricating a grid without line crossings) Fabrication time estimation Transformations. Allows to rotate object in XYZ space. Camera command Camera superposition view on top of fabrication view Sample tilting detection Free SCA Intro version for writing algorithms Data import from txt files Write to file Shape finder. Sample detection using sample edges(ex. sample corner position and angle can be detected using 2 or 4 sample edges). Shape finder includes Circle (radius and position), Corner(position and angle) finder. line template finder. It is used for line based pattern detection Pixel intensity based pattern matching. Manual alignment point selection. Autofocus tool: scan range and adjust modes Automatic and manual calibration Easy integration into SCA algorithm via FindFocus, Find Object, MV reference and Transform commands
S-waveplate Radial/Azimiuth Polarization Converter (RPC) S-waveplate is a super-structured waveplate which converts linear polarization to radial or azimuthal polarization. The product is unique for its high damage threshold 100 times exceeding alternative devices*. Unique results achieved by forming birefringent nanogratings inside a bulk fused silica glass. Enabling technology was developed by Prof. Peter G. Kazansky group from Optoelectronics Research Centre at Southampton University.
Applications Radial polarization enables focusing of laser beam into smaller spot size (with high NA>0.9 optics). For polarization direction sensitive applications radial and azimuth polarization allows same machining properties in all directions. Azimuth polarization remains ring shaped in focus plane so it is applicable in optical tweezers, STED microscopy or other depletion applications.
2.4. Special Optics
Standard S-waveplate models are available for 1030 nm, 515 nm, 800 nm and 1550 nm wavelengths. Dielectric anti-reflection coatings can be applied on both converter sides to further increase converter transmission. Custom wavelength (from 400 nm to 2000 nm) converters are available at request.
Features: Converts linear polarization to radial or azimuthal Can be used to create an optical vortex High damage threshold 100% polarization conversion 55-90% transmission (wavelength dependent) Large aperture possible (up to 10 mm or bigger; standard is 6 mm) No glued components – more resistant to heat No “ineffective center” problem Continuous pattern - no segment stitching
Fig. 2.4.2. Measured Gauss beam intensity distribution (left), S-waveplate (center), radial/azimuth polarization beam intensity distribution after S-waveplate.
* According to ISO 11254 – 2 is θ1000-on-1= 22.80 ± 2.74 J/cm2, at λ = 1064 nm, τ = 3.5 ns, f = 10 Hz.
Fig. 2.4.1. S-waveplate fabricated for 632 nm, clear aperture 8 mm.
Production of custom polarization converters is based on unique laser nano-structuring technique developed by prof. Peter G. Kazansky group from Optoelectronics Research Centre at Southampton University.
Features custom birefringent patterns wavelength range from 400 nm to 2000 nm half-wave or quarte-wave converters available size from 1 mm to 10 mm transmission from 40% to 90% (* wavelength dependent)
Volume Bragg Gratings (VBG) are formed in fused silica using direct laser writing technology based on femtosecond Gauss-Bessel beams. According to the VBG theory, they can reach the highest efficiency operating only at Bragg diffraction conditions, that can be expressed as: mλ ⁄n = 2dsin(ΘB) here ΘB is the Bragg angle, d is the period of the grating, λ is the wavelength of diffracted beam, and n is the refractive index of material where diffraction takes place. For a particular grating and single wavelength there exist several Bragg angles connected through the integer m; however, the condition that incident and diffracted beam angles have to be the same can be satisfied only once, thus energy interchange takes place only between diffracted and undiffracted. Features: Absolute diffraction efficiency up to 99% Refractive index modulation of up to 0.003 Up to 1000 lines/mm Thickness of the grating of up to few millimeters Custom shape and size of the grating is available on request. y n1 = 1
n2 = 1,46
Custom birefringent patterns (half-wave or quarter-wave) for tailored polarization conversion. We control retardance and slow axis angle according to the predefined pattern. We offer custom polarization converters for various polarization and beam shaping applications: radial, azimuth, random, circular, elliptical or even custom polarization, optical vortex generation, flattop generation.
Θm = ΘB
Θdtƒ = ΘB
Diffracted beam t
Fig. 2.4.4. Bragg grating model and Bragg grating fabricated in fused silica substrate.
Fig. 2.4.3. Custom birefringent patterns
Beam Shaping Unit is applied in laser systems for micromachining applications to create round or square laser spots with uniform intensity distribution.The BSU-6000 is developed to operate in combination with customer’s scanning optics, but can also be offered as a complete system. It is based on refractive field mapping beam shaper piShaper.Output of the piShaper is imaged onto a workpiece by imaging optical system composed from an internal collimator and external lens, for example F-theta lens of the customer’s equipment.
Requirements for the laser and optical scheme before installation The optical scheme with all explanations represents requirements that must be met before the unit installation.
2.5. Beam Shaping Unit
Requirements for the Customer‘s Laser Wavelength Average power Pulse duration Mode structure Intensity distribution
257-2050 nm up to 200 W CW ns, ps, fs TEM00 or multimode Gaussian or similar
Fig. 2.5.1. Example of beam shaping: Left: input laser beam, Right: final square spot. Final laser spot size and shape depend on customer‘s requirements.
Front (input) view
250 250 585 585
Fig. 2.5.2. Front and back side view
Back (output) view
Fig. 2.5.3. Side and top view All dimensions are in millimeters.
6.3 – 6.4 mm 50 mm 6000 mm πShaper 6_6 (unit type dependent) Depends on aperture shape - depends on magnification of the composed imaging system being defined as ratio of focal lengths of F-theta lens and internal collimator, - variable in case of Iris diaphragm
Input beam diameter Optical axis height (from bottom) Focal length of internal collimator Beam shaper model Spot shape Spot size
Dimensions (LxWxH) Input aperture diameter Output aperture diameter Weight Aperture placement Mounting points
585x251x97 mm 20 mm 20 mm < 6 kg see figures 2.6.2, 2.6.3 see figures 2.6.2, 2.6.3
2.7. Sample Holder
Designed in WOP laboratories for holding wide variety of samples during micromachining. It proved to be very versatile and convenient in operation.
Porous stone sample holder has uniform vacuum chuck surface, two axis tilting screws to compensate the sample position deflection. Rigid and durable design guarantees long period of exploitation.
Beam expander performance 0.50
Effective focal length Angular magnification
0.45 0.40 0.35 0.30
Features Standard size: 50x50 mm, 100x100 mm, diameter 152 mm Available in various shapes and sizes Available with pore size from 6 to 120 μm High porosity 40-50% Has a mechanical accurate tilting platform Good chemical, wearing and erosion resistance Can be used in high temperature environment
-5000 -6000 20
Porous stone sample holder
Selectable vacuum chucking places Robust steel or stainless steel construction Place for bottom lighting Integrated LED Place for fiber fastening XY tilting screws
Specifications Continuously variable magnification: 2,5x…12x Wavelength range (different on request): 1020 – 1070 nm 510 – 540 nm 340 – 360 nm Material: Optical crown glass or UV grade fused silica Control interfaces: USB 2.0; UART (RS232); Step/Dir Software platform: WindowsTM Entrance beam diameter: up to 10 mm Output beam diameter: up to 48 mm Overall transmission: 98.5 % LIDT: >7 J/cm2 for 10 ns pulses @ 1064 nm Weight: 1 Kg Applications Laser beam size control in industrial and scientific applications, laser machining systems Automatic control of focusing parameters (Numerical Aperture) Hands free operation in remote machinery places and hazardous conditions
Steel sample holder
Features Aberration minimized design (special aberration compensation layout) Plug & play solution (controller included) Suitable for ultrafast picosecond and femtosecond lasers Direct control from microcontrollers and embedded systems Optional adjustable mounting interface Individual calibration capability Individual presets for magnification Reduced setup time by automatic magnification adjustment Manual magnification control
0.15 0.10 15
7.5 4.8 Magnification
3.1. Glass/Sapphire Cutting WOP glass cutting technology Workshop of Photonics has developed a new state of the art technology glass and sapphire cutting technology to meet new challenges arising from new materials and requirements. Our technology enables dicing glass or sapphire from 30 μm to 1.3 mm (tested) thick with process speeds from 100 to 1000 mm/s depending on specific requirements. Straight and curved cuts can be performed at the same step with same or similar parameters.
3. Laser Micromachining Case Studies
Non temperred glass and sapphire: 1. A flat sheet of glass/sapphire has to be positioned under the laser beam in the aproximate beam focus distance. 2. Cuts are done by positioning glass/sapphire sheet under the laser beam. Depending on the thickness of sample, one or two passes per trajectory might be needed. 3. Surface position tracking is advised for large area samples. Hardware solution for the surface tracking may be provided by Workshop of Photonics. 4. Since non tempered glass and sapphire do not have internal tension, cleaving does not happen on itself and has to be initiated. This can be done mechanically (bending sheet allong the scribing lines) or a different method might be developed.
200 μm Fig. 3.1.1. Tempered glass 0.55 mm thickness, 42 µm DOL. Top view.
Fig. 3.1.2. Tempered glass 0.55 mm thickness, 42 µm DOL. Side view.
Fig. 3.1.3. Sapphire 0.325 mm thickness. Top view.
Fig. 3.1.4. Sapphire 0.1 mm thickness. Side view.
Tested glass and sapphire samples Technology was tested on a variety of glass and sapphire samples provided by various suppliers. List of the samples successfully tested to date, are provided below. Table 1. List of tempered glass samples tested No. 1. 2. 3. 4. 5. 6. 7. 8. 9.
Sample brand Not provided Gorilla glass Gorilla glass Gorilla CS Gorilla CS Not provided Gorilla glass Not provided Not provided
Thickness, µm 550 550 700 700 800 800 1100 1300 850
DOL, µm 30 42 42 23 23 30 10 30 7
Tempered glass: 1. A flat sheet of glass has to be positioned under the laser beam in the approximate beam focus distance. 2. Cuts are done by positioning glass sheet under the laser beam. Depending on the thickness of glass, one or two passes per trajectory might be needed. 3. Surface position tracking is advised for large area samples. Hardware solution for the surface tracking may be provided by Workshop of Photonics. 4. Sheet of glass is removed from the machine. Two alternatives are possible for cleaving: a. Initiation of self cleaving, by creating temperature gradient in the sample – slightly heating or cooling one side of the sample (please see video for an example). b. Sample can be left for several minutes untill self-cleaving happens without initiation.
Table 2. List of non-tempered glass samples tested No. 1. 2. 3. 4. 5. 6. 7. 8.
Sample brand Schott Schott Not provided Not provided Cornin Eagle glass Gorilla Gorilla Soda Lime glass
Workshop of Photonics developed a special technology for PZT ceramics fabrication. Thickness, µm 30 100 300 520 300 700 550 700
The fabrication comprises: Processing a heat sensitive material with no heat affected zones and melting layers Fabricating grooves of less than 15 µm widths and more than 25 µm depth. Fabricating grid of groves with no overshooting in intersections Fabricating grid of grooves within an existing pattern, with better than 0.5 µm accuracy within 40 mm area. Fabricating up to 9 samples without any operator interference Controlling the fabrication process for up to 24 hours long and maintaining needed accuracy, compensating beam and mechanical drift within 0,5 µm.
3.2. Ceramics Scribing
Table 3. List of sapphire samples tested
Thickness, µm 100-760 420 420
Processing parameters Process is optimized for each type of glass/sapphire that is used. Processing window is quite wide and can be set up easily according to these parameters: Straight and round cut trajectories; Thickness of tempered glass: 0.5 – 1.3 mm; DOL of tempered glass: 15 – 42 µm; Thickness of non-tempered glass: 30 – 500 µm; Thickness of sapphire: 100 – 760 µm; Speed of cutting (tested): 200 mm/s; Speed of cutting (extrapolated): 800 mm/s; Cut surface roughness: Ra<1 µm. Different processing parameters might be developed for specific inquiries.
Sample brand Crystaline sapphire Sapphire with ink layer (black, white) Sapphire with AR coatings
20 μm Fig. 3.2.1. Top view of scribed ceramics.
No. 1. 2. 3.
TGV – through glass vias is another example of industry driven development at Workshop of Photonics. This technology is used in semiconductor applications to connect several layers of stacked microchips. New an innovative beam positioning method was created by our engineers to achieve industrial quality requirements.
3.3. Through Glass Via (TGV) Drilling Processing of solar cells Applications: Front contact formation Back contact formation
This technology is currently under development, current specifications is subject to change in the future. Specifications Hole diameter 60 µm 30 µm 60 µm
Elipticity < 4 µm < 4 µm < 5 µm
Taper ~3 deg ~3 deg ~ 3.5 deg
Speed 0.25 s/hole 0.25 s/hole 0.22 s/hole
Edge isolation for solar cells
Selective dielectric layers removal for solar cells
Material glass glass sapphire
Thickness 100 µm 50 µm 100 µm
Fig. 3.3.1. Matrix of holes in glass.
100 μm Fig. 3.3.2. Matrix of holes in sapphire.
Laser marking of solar cells
Developed in cooperation with Swinburne University, Australia
Steel foil μ-drilling No melting Micron diameter Applications: Filters Functional surfaces
Marking of contact lens Marking made inside a bulk of contact lens, preserving surface of lens and distortions Exact positioning of markings – 3D text format
Ablation of PCD (polycrystalline diamond) Ablated circle crater on the surface of PCD Smooth and even bottom of the crater Application: Component of PCD cutting tools
Cast iron ablation Surface texturing with micro holes and grooves Minimum heat affected zone
Diamond cutting Low carbonization No HAZ Low material loss Applications: Diamond sheet cutting Diamond texturing/patterning
Metal micromachining 3D structures formed on steel surface High precision and surface smoothness achieved
Application: Friction reduction between moving metal parts
Applications: Microfluidic sensors Waveguides
Application: Detection of materials with increased sensitivity using surface-enhanced Raman scattering (SERS) Bio-sensing, water contamination monitoring, explosive detection etc.
Micro channel formation Wide range of materials – from glass to polymers
Nano ripples Up to 200 nm ripple period fabricated using ultra-short laser pulses Individual nano-feature size on ripples: 10 – 50 nm Controlled period, duty cycle and aspect ratio of the ripples
Product counterfeit protection Development of novel products
Applications: Solar cell production Semiconductor industry
100 μm Top view
Glass holes Various hole sizes with routine tapper angle better than 5 deg Minimal debris around the edges of holes
Silicon laser assisted etching No HAZ No melting
Datamatrix Data inscribed on a glass surface Extremely small individual elements, up to 5 µm in size 100 μm
Stent cutting Holes in stent wall, cross-section view Polymer stent No heat effect, no debris Minimal taper effect
Hologram production Example: hologram view generated using glass sample
Application: Vascular surgery
Appplication: Selective coating Glass tube drilling Controlled damage and depth
Mask for beam splitter pattern deposition Borosillicate glass 150 um thickness ~900 holes per mask Mask diameter 25,4mm
Application: Product marking
Applications: tissue biopsy equipment 15 μm
Selective metal coating ablation (removal) Selective ablation of metal coatings from various surfaces Depth and geometry of ablation may vary
Wood marking No heat effect, no signs of burning Application: Laser marking processes in highly flammable environments Decoration Counterfeit protection
Application: Lithography mask production Beam shaping elements Optical apertures Other
Texturized sapphire surface Micron resolution Large area processing Single pulses used to form craters on the surface
Amplitude grating formation
Application: Better light extraction in LED Semiconductor structure growth
Titan coating selective ablation
Chrome ablation for beam shaping
5 μm 50 μm
50 μm 2 μm
Marking inside a bulk of transparent material Colorful structures due to small pixel size Surface not affected Very small or no cracks near markings Low influence on strength of the substrate
Marking, patterning capabilities: Smallest spots up to 3 µm in width Micron level positioning No heat effect
Chrome ablation from glass substrate
Apperture array fabrication
Gold layer removal without damage to MgO substrate – Au layer removal without damaging
Applications: Optical fiber sensors Material science
Application: Consumer electronics MEMS systems
Optical fiber scattering No impact on fiber strength No surface damage Even light dispersion Products
Applications: Medical fibers Oncology
Optical fiber lensed using MPP technique Matching refractive index Shape flexibility Resolution from 100 nm to 20 μm
Glass micro-hole drilling (50/25 µm diameter) Glass 320 µm thick Hole entry diameter: 50 µm Hole exit diameter: 25 µm High hole quality
Applications: Medical fibers Fiber collimators
Serial production of micro-parts Submicron precision micro parts made of polycarbonate/polypropylene/poly(ethylene terephthalate) Minimal or no signs of heat effected deformation Excellent cut surface quality, sub-micron precision of shape High speed laser processing
Optical fiber drilled to the middle Diameter from <10 μm Various hole profiles possible Depth and angle control
How does multiphoton polymerization work? Multiphoton polymerization (MPP) is a unique technology for 3D structuring of micron scale objects with nanometer precision. Femtosecond laser beam is focused inside a drop of sol-gel or other types of photoresist polymer and desired pattern is “written” precisely point–by-point (Fig. 1 a and b). Then, the unsolidified remainder of the photoresist is washed away leaving only the fabricated microstructures on the substrate (Fig.1 c). Products
Features: 100 nm – 10 µm writing resolution Medium cost per sample Variety of polymers Complex 3D objects a)
Photoresist Polymer Materials Variety of photoresist materials with required features can be chosen; No structural distortions; Certain wavelength absorption; Refractive index matching.
< 90 nm
Precision and Controllable Self-Polymerization Standard direct writing is able to make repeatable structures as small as 100 nm, though by employing self-polymerization effect, the smallest lines can be around 20 nm. This effect occurs when certain distance between polymerized structure walls is kept, so self-polymerizing structures can be controlled, at least to some extent. Repeatability
Reliable and multifunctional software SCA Professor ensures fast preparation, stable workflow. 3D lithography is related to huge amounts of data, which has to be transmitted between computer and positioning controllers. Many systems crash because of poor software adaptation to these specific tasks. SCA professor splits the data in portions to deliver them safely and timely to the controllers. Moreover, identical structures can be fabricated by direct laser writing process but in order to save time and work for large area patterning stamping technique can be used.
What is a “technological platform”? Technology
Co-development with Vilnius University Laser Research Center.
MPP technological platform can offer a flexible solution for micro prototyping and production. It is a combination of feasibility studies, small-scale production and development of turn-key work stations. This platform includes certain steps from selecting the most suitable photoresist to building task-dedicated laser system for science or industry.
The SCA laser automation software product family procides speed, visibility and efficiency to multiphoton polymerization operations and other laser micromachining tasks. The software is distinguished among other existing laser software solutions by the key working principle – it controls positioning stages by directly addressing the command libraries of the positioning stages software (no machine code conversion). Structures of any geometry can be fabricated directly from CAD file. There are no limitations for object shape or direct writing geometry, except those limited by obvious laws of physics.
Laser system software SCA
3.5. Multiphoton polymerization
Main Applications: Microoptics Photonic crystals Regenerative medicine 36
More information at http://www.wophotonics.com/applications/
* Illustration Reference
1, 3. Mangirdas Malinauskas, Arune Gaidukeviciute, Vytautas Purlys, Albertas Zukauskas “Direct laser writing of microoptical structures using a Ge-containing hybrid material” Metamaterials 5 (2011) 135–140
Commercial partners Our solutions often incorporate products and know-how of Lithuanian and foreign laser companies:
2. MangirdasMalinauskas, Holger Gilbergs, Albertas Zukauskas, Vytautas Purlys, Domas Paipulas, Roaldas Gadonas, “A femtosecond laser-induced two-photonphotopolymerization technique for structuring microlenses” J. Opt. 12 (2010) 035204 (8pp)
4, 5. M. Malinauskas, V. Purlys, M. Rutkauskas, A. Gaidukeviciute, R. Gadonas “Femtosecond Visible Light Induced Two-Photon Photopolymerization For 3d Micro/Nanostructuring In Photoresists And Photopolymers” Lithuanian Journal of Physics, Vol. 50, No. 2, pp. 201–207 (2010)
6, 7. Mangirdas Malinauskas, Albertas Zukauskas, Vytautas Purlys, Kastytis Belazaras, Andrej Momot, Domas Paipulas, Roaldas Gadonas, Algis Piskarskas, “Femtosecond laser polymerization of hybrid/integrated micro-optical elements and their characterization” J. 2010 J. Opt. 12 124010
8, 9, 10. Etienne Brasselet, Mangirdas Malinauskas, Albertas Zukauskas,Saulius Juodkazis Photo-polymerized microscopic vortex beam generators : precise delivery of optical orbital angular momentum Appl. Phys. Lett. 97, 211108 (2010); doi:10.1063/1.3517519
11, 12. Mangirdas Malinauskas, Holger Gilbergs, Vytautas Purlys, Albertas Žukauskas, Marius Rutkauskas and Roaldas Gadonas, “Femtosecond laser-induced two-photon photopolymerization for structuring of micro-optical and photonic devices” Proc. of SPIE Vol. 7366 736622-1 (2009)
13, 14, 15, 16. M. Malinauskas, P. Danilevicius, D. Baltriukiene, M. Rutkauskas, A. Žukauskas, Ž. Kairyte, G. Bickauskaite, V. Purlys, D. Paipulas,V. Bukelskiene, R. Gadonas “3d Artificial Polymeric Scaffolds For Stem Cell Growth Fabricated By Femtosecond Laser” Lithuanian Journal of Physics, Vol. 50, No. 1, pp. 75–82 (2010)
Academic partners The company strives to bring new inventions from academia into market. Therefore, we invest time and effort into building mutually beneficial academic partnerships: Vilnius University, Lithuania: micromachining research and applications. Kaunas University of Technology, Lithuania: coatings, lithography and microfabrication. Swinburne University of Technology, Australia: SERS sensors for Raman spectroscopy development. University of Southampton, United Kingdom: development of special optics. University of Insubria, Italy: femtosecond micromachining using non-Gaussian beams. Tampere University of Technology, Finland: joint development of OPSL yellow laser.
17, 18, 19, 20. M. Malinauskas, P. Danilevicius1, A.Zukauskas1, G. Bickauskaite,V. Purlys, M. Rutkauskas, T. Gertus, D. Paipulas1, J. Matukaite, A. Kraniauskas, R. Sirmenis, D. Baltriukiene, V. Bukelskiene, R. Gadonas, V. Sirvydis, A. Piskarskas “Laser 3D Micro/Nanofabrication of Polymers for Tissue Engineering Applications” Latvian Journal Of Physics And Technical Sciences 2011, Nr. 2
21. M. Malinauskas,P. Danilevicius, A. Zukauskas, D. Paipulas, V. Purlys, R. Gadonas, A. Piskarskas D. Baltriukiene, R. Jarasiene, V. Bukelskiene, A. Kraniauskas, R.Sirmenis, V. Sirvydis. “Biocompatibility of polymers and laser-fabricated three-dimensional microstructured polymeric scaffolds for biomedical applications” Submitted for “Engineering in Life Sciences” journal October 11, 2010
Participation in Exhibitions
4-6 February 2014, San Francisco, USA
18-20 March 2014, Shanghai, China
20-22 May 2014, Tel Aviv, Israel
17-20 June 2014, Vilnius, Lithuania
24-26 June 2014, Stuttgart, Germany
Mokslinink킬 st. 6A 08412 Vilnius, Lithuania
tel. +370 5 272 57 38 fax +370 5 272 37 04
Published on Mar 25, 2014