Laser micromachining solutions
2015
Workshop of Photonics速 is all about laser micromachining. We develop instruments and solutions for laser micromachining tasks. From feasibility studies to customized optical modules and from electronic devices to laser machines. Our services are targeted to both industrial and academic customers. Our key competencies: Feasibility studies on femtosecond laser micromachining Development of custom femtosecond laser micromachining workstations and optical modules Laser system automation software Our competence growth is fueled by culture of open innovations and partnership with the Lithuanian laser sector companies and worldwide partners. Workshop of Photonics is constantly working on projects connecting scientific inventions with the industry needs.
For more information please visit www.wophotonics.com
Content
1. Services.
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1.1. Feasibility Studies. .
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1.2. Laser Process Development. . 2. Products..
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2.1. Laser Systems for Laboratories.. 2.2. Industrial Laser Machines. 2.3. Special Optics..
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2.4. Beam Shaping Unit .
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2.5. WOP module for cutting glass and sapphire. . 3. Technology.
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3.1. WOP laser technology for cutting glass and sapphire.. 22 3.2. Heat Sensitive Materials Scribing..
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3.3. Through Glass Via (TGV) Drilling..
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3.4. 3D Additive Manufacturing. . Micromachining Examples. Partners.
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Services
1. Services Workshop of Photonics cooperation with customer usually starts with a demand to perform a specific micromachining task. The first step is a feasibility study which means that our company prepares samples for a customer to showcase achieved results and prove feasibility of laser processing. Regarding customer requirements it may lead to a small scale production if this is only a one time request. For a more demanding customer feasibility studies would lead to a laser process development - the solution how to prepare the samples would be developed together with a customer. Pinnacle of the cooperation with the customer is designing and manufacturing custom system for a laser micromachining task. It is a customer’s choice how far to go down the steps of cooperation with Workshop of Photonics.
Products
Feasibility study
Laser process development (laboratory prototype)
Small scale production
Design of a system/module
Custom laser systems for science
Laser Machines for Industry*
Warranty, maintenance & technological support Technology
* In partnership with manufacturing machinery producers
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The essence of feasibility study is to demonstrate that customer’s problem can be solved using ultrashort pulsed laser micromachining technology and that it has advantages over competing technologies. Workshop of Photonics laboratories are fully equiped and ready to process various materials with femtosecond and picosecond lasers and achieve desired results.
Services
1.1. Feasibility Studies
1.2. Laser Process Development Most of laser micromachining applications are not as straightforward as for example marking. Most of them require development that takes weeks and even months.
Products
Feasibility studies are performed in following steps: 1. Detailed task description 2. Samples 3. Processing 4. Evaluation of results 5. Preparation of report 6. Feedback from customer
A typical approach for a comprehensive process development contains following steps: testing of different wavelengths in order to explore light-material interaction testing of different focusing conditions selecting and testing most suitable positioning solution determining what is required for repeatability and required speed of process optimizing software functionality for convenient process control
Technology
Not only different laser parameters have to be tested but also various beam shaping and focusing solutions.
Every customer is welcome to contact us with specific micromachining tasks. We are committed to develop a micromachining process. If a task is more demanding, we are ready to involve our academic partners in search of a solution. For more examples of our work please see page 30. 5
2. Products Services
2.1. Laser Systems for Laboratories
Products
Workshop of Photonics develops customized laser micromachining workstations - devices that fully meets customer’s requirements. Based on customer’s requiremnts 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 Sample handling automation (optional) Optical table Enclosure Dust removal unit We provide a custom solution for every laboratory. A proven flexibility of FemtoLAB concept allows to further expand and upgrade the system when new requirements arise.
FemtoLAB
Technology
FemtoLAB is a femtosecond laser micromachining system for scientific laboratories. Equipped with high accuracy linear positioning stages, high performance galvanometer scanners and versatile micromachining software SCA, FemtoLAB becomes an entire laser laboratory on an optical table.
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Features: Custom design End user selected laser source Efficient beam delivery and power control Highest quality optical components High accuracy positioning stages Additional non-stadard equipment can be integrated on request
Services
Specifications for a femtosecond laser based system: Pulse duration (from 200 fs to 10 ps) Repetition rate (from 1 kHz to 1 MHz) Average power (up to 15W) Pulse energy: up to 2 mJ Wavelengths (1030 nm, 515 nm, 343 nm, 258 nm, 206 nm) Positioning accuracy: Âą250 nm Travel range: customer selected
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Products
Applications: surface micro and nanostructuring, engraving, drilling, laser lithography and multiphoton polymerization, refractive index modification inside bulk of material, selective layer removal, cutting brittle materials, waveguide fabrication, your task.
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FemtoLAB-MPP Services
FemtoLAB-MPP workstation is optimized for multiphoton polymerization (MPP) technology. System layout and design is similar to standard FemtoLAB which can also be used for MPP application after minor modifications. 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 Market available photoresists
Products
FemtoLAB-KIT FemtoLAB kit is a unique femtosecond micromachining system which can be installed next to customer’s femtosecond laser source. Depending on laser specifications this system can become a universal tool for micromachining of different materials. Machine vision and user friendly software allows to perform various micromachining tasks easily. 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 Technology
Applications Optional features: (*depends on customer’s 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) Custom device integration 8
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.
Services
FemtoFAB
Specifications: Task optimized, available range is similar to FemtoLAB (see page 7) Applications: Ceramics scribing, glass cutting, sapphire cutting, TGV drilling, solar cell manufacturing, birefringent pattern fabrication, etc.
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Features: High fabrication speed – up to 300 mm/s (more on request) Fabrication of complex 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
Needs of industrial customers are rather different from those from an academic laboratory: speed, repeatability and efficiency are in focus. The whole system has to be built around process. Therefore our laser solution mostly is a part of a bigger manufacturing machine or production line. Usually it is built by specialized integrators or producers of manufacturing machinery. Workshop of Photonics develops laser micromachining process and implements it into customer’s production line or designs specialized workstation. System configuration will be selected to assure quality, speed and reliability of execution of the task. In order to automate the fabrication process, a custom adaptation of our laser micromachining software SCA engineer can be designed. 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.
Technology
2.2. Industrial Laser Machines
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Laser Micromachining Software SCA
Services
Laser Micromachining Software SCA provides speed, flexibility and visibility to laser micromachining operators. It makes fabrication tasks easy to write, fine-tune and repeat
Products
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 controls a wide range of equipment Customizable to fit special requirement of scientific or industrial applications 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 Versions of the software: SCA Professor:
Technology
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 Real-time sample view through camera Complex machining tasks
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SCA Student:
Dedicated to control basic micromachining systems Control of 2 positioning axis / galvoscanners Live sample view through camera
Dedicated for fabrication recipe preparation Free of charge Complete functionality for recipe preparation Does not connect to hardware to control it
Products
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
Services
SCA Intro:
SCA Engineer:
Technology
Fig. 2.2.1. Cross-hatched shape prepared for 2.5D fabrication
Fig. 2.2.2. Machine vision automatically recognizes glass substrate and positions fabrication trajectories in the center of it
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2.3. Special Optics Services
S-waveplate - Radial/Azimuthal Polarization Converter (RPC) S-waveplate is a spatially variable waveplate which converts linear polarization to radial or azimuthal polarization. The product is unique for it’s high damage threshold 100 times exceeding alternative devices*. Unique results are achieved by forming birefringent nanogratings inside a bulk of fused silica glass. Product developed in collaboration with Prof. Peter G. Kazansky group from Optoelectronics Research Centre at Southampton University.
Technology
Products
* 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.
Features: Converts linear polarization to radial or azimuthal Converts circular polarization to optical vortex High damage threshold 55-90% transmission (wavelength dependent) Large aperture (up to 15 mm; standard is 6 mm) Continuous pattern - no segments
Fig. 2.3.1. S-waveplate fabricated for 632 nm, clear aperture 8 mm. Cross polarized light photo
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Services
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.
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=
Technology
Applications STED microscopy Micromachining Microdrilling high-aspect-ratio channels Generate any cylindrical vector vortex Multiple particle trapping Micro-mill driven by optical tweezers Use as intracavity polarization-controlling element in cladding-pumped ytterbium doped Observation of photonic spin Hall effect with rotational symmetry breaking Realization of polarization evolution on higher-order PoincarĂŠ sphere Direct transformation of linearly polarized Gaussian beam into vector-vortex beams with various spatial patterns
Products
Fig. 2.3.2. Measured incident beam intensity distribution (left), S-waveplate (center), radial/azimuth polarization beam intensity distribution after S-waveplate
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Custom spatially variable waveplates
Services
We can fabricate custom spatially variable waveplates (half-wave or quarter-wave) for tailored polarization conversion and beam shaping. We can inscribe spatially varying fast axis angle pattern according to your function. Various custom spatially variable waveplates examples are shown in fig. 2.3.3.
Technology
Products
Features custom spatially variable fast axis and/or retardance patterns wavelength range from 400 nm to 2000 nm half-wave or quarter-wave converters available size from 1 mm to 20 mm transmission from 40% to 90% (* wavelength dependent)
500 Îźm
Fig. 2.3.3. custom spatially variable waveplate photos in crosss polarized light
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Volume Bragg Gratings (VBG) are formed in fused silica using direct laser writing technology based on femtosecond Gauss-Bessel beams. 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
n1 = 1
z
n2 = 1,46
d
Θm = ΘB
Transmited beam
Θdtƒ = ΘB
Incident beam
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y
Services
Bragg Gratings
Diffracted beam t
Fig. 2.3.5. Bragg grating fabricated in fused silica substrate
Technology
Fig. 2.3.4. Bragg grating model
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2.4. Beam Shaping Unit Services
BSU-6000 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 πShaper.
Products
Output of the πShaper 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.
Fig. 2.4.1. Example of beam shaping: Left: input laser beam, Right: final square spot. Final laser spot size and shape depend on customer‘s requirements
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50
97
36,5 36,5
Side view
Front (input) view
175 175
250 250 585 585
25,5 25,5
200 200
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206,5 206,5
Top view
251
Back (output) view
*All dimensions are in millimeters. Fig. 2.4.2. Front and back side view
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Fig. 2.4.3. Side and top view
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
Services
Requirements for the Customer‘s Laser
Input beam diameter Optical axis height (from bottom) Focal length of internal collimator Beam shaper model Spot shape Spot size
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
Products
Optics
Mechanics 585x251x97 mm 20 mm 20 mm < 6 kg see figures 2.5.2, 2.5.3 see figures 2.5.2, 2.5.3 Technology
Dimensions (LxWxH) Input aperture diameter Output aperture diameter Weight Aperture placement Mounting points
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BSU-8000
Services
Beam Shaping Unit 8000 is intended to be applied in laser systems for various micromachining applications to create round or square laser spots with uniform intensity distribution. BSU-8000 was developed by AdlOptica and technically implemented by Workshop of Photonics. The BSU-8000 is developed to operate in combination with customer’s scanning optics and is based on refractive field mapping beam shaper πShaper.
Products
Output of the πShaper is imaged onto a workpiece by imaging optical system composed from an internal optics and external lens, for example F-theta lens of the customer’s equipment.
Fig. 2.4.4. Intensity profiles a) Input TEM00 b) Output beam profile
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Technology
*All dimensions are in millimeters. Fig. 2.4.5. Bottom and side view of BSU-8000
Output beam mirror mount. Can be rotater by 90°, so exit beam can be rotated up/down/left/right
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Specifications
Flattness of flat top Final spot diameter (on the focus plane of F-theta) Final spot diameter (on the focus plane of F-theta) Dimensions (LxWxH) Distance from BSU to scanning head Weight
πShaper 4.5_4.5_1064 (unit type dependant) 8000 mm <15% (losses due to the additional apertures not included) >95% for TEM00 beam, M2<1.1, to be evaluated additionally for M2>1.1 56±6 um (<10% variation) 90±9 um (<10% variation) Approximately: 690x400x100 mm 500-1000 mm 20 kg
Additional components Mount for fixing apertures Fized size square aperture A set of fixed diameter round apertures (5 pieces):
Services
20 mm 0.7x...1.3x 4.5 mm
Mechanical with fixing screws (M6) Diagonal 4.4 mm, different available on request Diameter 4,0-4,4 mm, with 0,1 mm step
Products
Input and output aperture diameters Zoom Beam Expander Output beam diameter from beam expander Beam shaper model Focal length of internal collimator Power losses
Fig. 2.4.6. A principal optical scheme of BSU installation
A principal optical scheme of BSU installation is demonstrated in Fig. 2.5.6. The mirrors, marked by letter M and M‘, are to be installed prior the installation of BSU. It is just to imagine how optical path should be prepared in advance. Mirrors M‘ are removed during the installation and replaced with the BSU. Please consider that mirrors M1 and M2 before the enatrance of the BSU are necessary to allow proper alignement of the beam. Two mirrors M3 and M4 after the exit of BSU they are necessary for proper beam alignement to the scanner unit. The distance between a couple of mirrors should be at least 200 mm.
Technology
BSU installation
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Services
2.5. WOP module for cutting glass and sapphire
Technology specifications
Products
Workshop of Photonics has developed a break through transparent material cutting technology, which enables: Scribing tempered, non-tempered glass and sapphire Irregular shape cutting High process speed ≥ 200 mm/s High throughput and yield Low chipping <20 μm for most materials Easy breaking for non-tempered glass and self breaking for tempered glass Smooth side walls after breaking, Ra<1 μm No debris on back and front surface Single pass process for glass up to 1 mm thickness Already tested with high DOL glass from 0.4 mm to 1.3 mm thickness DOL layer from 10 μm to > 40 μm. High bending strength Easy adaptation for different glass types Solutions for system integrators Technology
Transparent material cutting module specifications: Optimized for 1028 nm wavelength Sealed monolithic housing Integrated autofocus (AF) unit with 400 μm piezo axis for sample tilt compensation Integrated motorized linear axis with 15 mm travel, optional, eliminates the need of external Z axis Optional external Machine vision unit (not present in picture below) Optional alignment module for adjustment Dimensions HxWxD: 315x369x102 mm
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Services
1. Detachable alignment unit (DAU) â&#x20AC;&#x201C; for adjustment and for servicing procedures (alignment check). One DAU can be used for several modules 2. External Machine vision module. Includes objective (from 1.5x magnification) with coaxial light source GigE camera
1. 2.
3. 400 Îźm piezo stage for AF and 15 mm motorized internal linear Z stage for adjusment between different thickness glass
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3.
Integration For system integrators Workshop of Photonics offers easy to implement packages: Optical module and technology licence Optical module, technology licence and suitable laser source Standalone module mounting can be seen in the picture bellow: Two optional laser beam inputs
Technology
Mechanical stress free three point mounting with optional hard points for easy exchange
As an alternative optical head mounted on dedicated source can be offered. 21
3. Technology Services
3.1. WOP laser technology for cutting glass and sapphire Workshop of Photonics has developed a new state of the art 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 speed 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.
Technology
Products
Processing steps for tempered glass: 1. A flat sheet of glass has to be positioned under the laser beam in the approximate beam focus distance. 2. 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 watch the video on www.wophotonics.com). b. Sample can be left for several minutes untill self-cleaving happens without initiation.
200 μm Fig. 3.1.1. Tempered glass 0.55 mm thickness, 42 µm DOL. Top view
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Fig. 3.1.2. Tempered glass 0.55 mm thickness, 42 µm DOL. Side view
Services
Processing steps for non tempered 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. 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
50 μm
Fig. 3.1.3. Sapphire 0.325 mm thickness. Top view
Fig. 3.1.4. Sapphire 0.1 mm thickness. Side view
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100 μm
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.
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
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Table 1. List of tempered glass samples tested
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Table 2. List of non-tempered glass samples tested
Services
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
Thickness, µm 30 100 300 520 300 700 550 700
Table 3. List of sapphire samples tested
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No. 1. 2. 3.
Sample brand Crystaline sapphire Sapphire with ink layer (black, white) Sapphire with AR coatings
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: 10 – 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
Technology
Different processing parameters might be developed for specific inquiries.
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Workshop of Photonics developed a special technology for heat sensitive material processing.
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The fabrication comprises: No heat affected zones and melting layers Grooves of less than 15 µm widths and more than 25 µm depth No overshooting in intersections 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
Services
3.2. Heat Sensitive Materials Scribing
20 μm
Technology
Fig. 3.2.1. Top view of scribed ceramics
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3.3. Through Glass Via (TGV) Drilling Services
TGV – through glass vias is another example of industry driven development at Workshop of Photonics. This technology is used for semiconductor applications to connect several layers of stacked microchips. The new innovative beam positioning method was created by our engineers to achieve industrial quality requirements. This technology is currently under development, current specifications is subject to change in the future. Specifications Material glass glass sapphire
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
Products
Thickness 100 µm 50 µm 100 µm
20 μm
Technology
Fig. 3.3.1. Matrix of holes in glass
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100 μm Fig. 3.3.2. Matrix of holes in sapphire
Features: 100 nm – 10 µm writing resolution Medium cost per sample Variety of polymers Complex 3D objects
5 μm Fig. 3.4.1
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3D additive manufacturing, in other words multiphoton polymerization (MPP) is a unique technology for 3D structuring of micron scale objects with nanometer precision co-developed with Vilnius University Laser Research Center. 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. Then, the unsolidified remainder of the photoresist is washed away leaving only the fabricated microstructures on the substrate (Fig. 3.4.2).
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3.4. 3D Additive Manufacturing
Technology
Fig. 3.4.2
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Laser system software SCA
Services
The SCA laser automation software product family provides 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. Photoresist Polymer Materials Variety of photoresist materials with required features can be chosen No structural distortions Certain wavelength absorption Refractive index matching Precision and Controllable Self-Polymerization
< 90 nm
Fig. 3.4.4
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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
Technology
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.
2 μm
Fig. 3.4.5
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Main Applications: Microoptics Photonic crystals Regenerative medicine
10 μm
Fig. 3.4.6
Fabrication examples 1. Conventional minimized optical components Prisms
Gratings
Segmented phase plates
Fresnel lenses fraxicons
Axicons Services
Lenses
Spiral phase plates
3. Arbitrary shape arrays of the Âľ - optical components with 100 % fill factor
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2. Free form 3D elements
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4. Complex shaped, multi-functional and integrated Îź-optics in a single fabrication procedure.
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Micromachining Examples Processing of solar cells Applications: Front contact formation Back contact formation
Edge isolation for solar cells
50 Îźm
Selective dielectric layers removal for solar cells For novel emitter side metalization technologies For PERC technology
30 Îźm
Laser marking of solar cells
10 Îźm
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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 Applications: Detection of materials with increased sensitivity using surface-enhanced Raman scattering (SERS) Bio-sensing, water contamination monitoring, explosive detection etc.
1 μm
Developed in cooperation with Swinburne University, Australia
Metal micromachining 3D structures formed on steel surface High precision and surface smoothness achieved 100 μm
Cast iron ablation Surface texturing with micro holes and grooves Minimum heat affected zone Application: Friction reduction between moving metal parts
200 μm
Marking of transparent materials bulk Marking made inside a bulk of contact lens, preserving surface of lens and distortions Exact positioning of markings – 3D text format Applications: Product counterfeit protection Development of novel products
100 μm
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Micro channel formation Wide range of materials – from glass to polymers Applications: Microfluidic sensors Waveguides
Diamond cutting Low carbonization No HAZ Low material loss Applications: Diamond sheet cutting Diamond texturing/patterning
100 μm
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
100 μm
Steel foil μ-drilling No melting Micron diameter Applications: Filters Functional surfaces
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10 μm
Datamatrix Data inscribed on a glass surface Extremely small individual elements, up to 5 µm in size Application: Product marking
100 μm
Mask for beam splitter pattern deposition Borosillicate glass 150 um thickness ~900 holes per mask Mask diameter 25,4mm Application: Selective coating Glass tube drilling Controlled damage and depth
20 μm
Application: tissue biopsy equipment 15 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
100 μm Optical fiber
Sapphire
Glass
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Glass holes Various hole sizes with routine tapper angle better than 5 deg Minimal debris around the edges of holes Application: Microfluidics
100 μm Top view
Cross-section
Stent cutting Holes in stent wall, cross-section view Polymer stent No heat effect, no debris Minimal taper effect Application: Vascular surgery
100 μm
100 μm
Fuel Nozzle drilling: Special steel Controllable taper angle Variable geometry Application: Fuel delivery systems
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Marking, patterning capabilities: Smallest spots up to 3 µm in width Micron level positioning No heat effect
Metal
Hair
Wood marking No heat effect, no signs of burning Applications: Laser marking processes in highly flammable environments Decoration Counterfeit protection
Texturized sapphire surface Micron resolution Large area processing Single pulses used to form craters on the surface Applications: Better light extraction in LED Semiconductor structure growth
30 μm
5 μm
2 μm
10 μm
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Selective metal coating ablation (removal) Selective ablation of metal coatings from various surfaces Depth and geometry of ablation may vary Applications: Lithography mask production Beam shaping elements Optical apertures Other
Amplitude grating formation
100 μm Titan coating selective ablation
50 μm
50 μm Chrome ablation from glass substrate
Optical fiber drilled to the middle Diameter from <10 μm Various hole profiles possible Depth and angle control Applications: Optical fiber sensors Material science
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Chrome ablation for beam shaping
Apperture array fabrication
Gold layer removal without damage to MgO substrate – Au layer removal without damaging
Optical fiber scattering No impact on fiber strength No surface damage Even light dispersion Applications: Medical fibers Oncology
100 μm
Optical fiber lensed using MPP technique Matching refractive index Shape flexibility Resolution from 100 nm to 20 μm Applications: Medical fibers Fiber collimators
200 μm
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 Applications: Consumer electronics MEMS systems
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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
25.1 μm
100 μm
51.3 μm
100 μm
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Partners Commercial partners Our solutions often incorporate products and know-how of Lithuanian and foreign laser companies:
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.
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Participation in Exhibitions
22-25 June, 2015, Munchen, Germany. Booth B3.405
13-18 February 2016, San Francisco, USA
15-17 March, 2016, Shanghai, China
Altechna R&D
Mokslinink킬 st. 6A 08412 Vilnius, Lithuania
tel. +370 5 272 57 38 fax +370 5 272 37 04
info@wophotonics.com www.wophotonics.com