My Research Adam Rosowski Photonic in Engineering
Photo onic in Engineering Motivation Chemical etching process Direct laser process HCL Technology Therahertz spectroskopy Physics
Motivation Photonic in Engineering http://www.dsod.pl
Motivation Photo onic in Engineering MEMS elements: Size: 1-200µm Materials: semicondutors (Si, SiC, GaAS, etc.), ceramics, glass, polymers Structures: membrans, cantilevers, channels, blades and another microdetails
State of art Photo onic in Engineering Present technologies: Wet chemical etching in solution (eg. KOH, NaOH, HNO 3 + HF) Dry physical etching (eg. RIE, laser)
Photo onic in Engineering Motivation Chemical etching process Direct laser process HCL Technology Therahertz spectroskopy Physics
Chemical etching in base Photo onic in Engineering Basic process: Si + 2(OH) - + 4H 2 O Si(OH) 6 2- + 2H 2 Speed of etching: V E = a V0 exp kt
Chemical etching in base Etch rate (µm/min) Photo onic in Engineering Echant Temperature Si (100) Si (110) Si (111) 40 0.188 20% KOH 60 0.45 80 1.4 100 4.1 40 0.108 0.16 30% KOH 60 0.41 0.62 80 1.3 2.0 0.005 100 3.8 5.8 40 0.088 40% KOH 60 0.33 80 1.1 1.294 0.009 100 3.1
Chemical etching Photo onic in Engineering Advantages: High quality of etched structures Batch-process low cost of one unit Disadvantages: Low speed of etching Lithography processes Difficulties with complex structures and different materials
Photo onic in Engineering Motivation Chemical etching process Direct laser process HCL Technology Therahertz spectroskopy Physics
Direct laser process Photo onic in Engineering Advantages: High speed of etching Direct process without lithography Simple for diffrent materials Disadvantages: Poor quality Difficulties with batch-process
Experimental setup Photo onic in Engineering SPI G3: 1070nm, 9-200 ns, 25-500kHz Coherent Avia: 355nm, 30ns, 25-100kHz Spectra-Physics Pantera: 355nm, 50ps, 80MHz
Direct laser process Photonic in Engineering
Photo onic in Engineering Motivation Chemical etching process Direct laser process HCL Technology Therahertz spectroskopy Physics
HCL technology Photo onic in Engineering Connection between chemical and laser etching: Laser direct processing and post-processing in solution; Laser ablation in solution; Chemical process activated and assited with laser beam: Laser beam increases local temperature of liquid and surface (higher etching rate) Laser beam decreases chemical activation energy locally Solution etches locally (high quality) Laser beam increases reactivity of OH - ions
HCL technology Photo onic in Engineering Advanatages: High quality High etching speed Direct process without lithography Simple for different materials (wide band gap semiconductors) and difficult structures Disadvanatages: Problems with batch-process
Experimental setup Photo onic in Engineering Processing chamber Pumping system Temperature control Scan head Laser: SPI G3 Specra Physics Pantera / Coherent Avia Diode laser Solution: KOH/NaOH
Results Chemical etching HCL technology Photonic in Engineering
Results Photo onic in Engineering Direct laser process HCL technology
Results - mistakes Photonic in Engineering
Photo onic in Engineering Motivation Chemical etching process Direct laser process HCL Technology Therahertz spectroskopy Physics
Terahertz radiation Photonic in Engineering
Art spectroscopy Photonic in Engineering Dr Michael Panzner
Time-domain spectroscopy Photonic in Engineering
Software Photonic in Engineering With Dr Michael Panzner
Results Photonic in Engineering With Dr Michael Panzner
Photo onic in Engineering Places of my research: Fraunhofer IWS, Dresden, Germany: 2008, 2009, 2011, 2012 Lappenranta Laser Processing Centre (VTT and University of Technology), Lappeenranta, Finland, 2009, 2010 Photonics in Engineering Group, Liverpool John Moores University, Liverpool, UK, 2010
Photo onic in Engineering Motivation Chemical etching process Direct laser process HCL Technology Therahertz spectroskopy Physics
onic in Engineering Relativistic transformation Lorenz transformation: where: Conclusions: ( ) = = 2 ' ' c vx t t vt x x γ c v = = β β γ, 1 2 2 0 1 ; v l l t t = = Photo How???? 2 0 2 2 1 ; 1 c l l c v t = = 2 0 2 0 0 1 1 β β = = = T T T T T T
Maxwell vs Jüttner Distribution Photo onic in Engineering We cannot measure (the black holes, the centre of stars, etc.)
Confirmation Photo onic in Engineering Computer simulation only 1D and 2D gases were done; 3D Monte Carlo only Problems: Huge number of balls Relativistic transformation (!) Definition of temperature Program: Method: deterministic model Environment: MatLab It has to work with huge numbers of balls Extreme optimisation of memory use and processor utilisation
Results Photonic in Engineering
Photo onic in Engineering Thank you for your attention Adam Rosowski (Adam.P.Rosowski@ljmu.ac.uk) www.ljmu.ac.uk/geri