doc3D nano- and micro-processing by femtosecond laser for photonics
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3D nano- and micro-processing by femtosecond laser for photonics
3D nano- and micro-processing by femtosecond laser for photonics applications PhAST Conference San Francisco, CA, 19 May 2004 Rafael Gattass Iva Maxwell Sam Chung Alex Heisterkamp and also.... Loren Cerami Eli Glezer Chris Schaffer Nozomi Nishimura Jonathan Ashcom Nan Shen Debyoti Datta Dr. André Brodeur Dr. Limin Tong Dr. Prissana Thamboon Prof. Donald Ingber (Childrens Hospital) Dr. Sanjay Kumar (Childrens Hospital) Prof. Philip LeDuc (Carnegie Mellon) Prof. Aravi Samuel (Harvard) Introduction Introduction Introduction Introduction use ‘damage‘ for processing! Outline Outline Processing with fs pulses Role of focusing Low-energy processing Processing with fs pulses 10–1 τ 1/2 Fth (J/m2) 10–2 τ –1 10–3 10–4 –1 10 100 101 102 103 pulse duration (ps) Du et al., Appl. Phys. Lett. 64, 3071 (1994) 104 105 Processing with fs pulses Processing with fs pulses “… clear evidence that no bulk plasmas ... [and] ... no bulk damage could be produced with femtosecond laser pulses.” von der Linde, et al., J. Opt. Soc. Am. 13, 216 (1996) Processing with fs pulses focus laser beam inside material 100 fs transparent material objective Glezer, et al., Opt. Lett. 21, 2023 (1996) Processing with fs pulses 2 x 2 µm array fused silica, 0.65 NA 0.5 µJ, 100 fs, 800 nm Opt. Lett. 21, 2023 (1996) Processing with fs pulses 2 x 2 µm array fused silica, 0.65 NA 0.5 µJ, 100 fs, 800 nm Opt. Lett. 21, 2023 (1996) Processing with fs pulses 2 x 2 µm array fused silica, 0.65 NA 0.5 µJ, 100 fs, 800 nm Opt. Lett. 21, 2023 (1996) Processing with fs pulses 2 x 2 µm array fused silica, 0.65 NA 0.5 µJ, 100 fs, 800 nm Opt. Lett. 21, 2023 (1996) Processing with fs pulses 100 fs 0.5 µJ 200 ps 9 µJ Processing with fs pulses 100 fs transparent material objective high intensity at focus… Processing with fs pulses 100 fs transparent material objective …causes nonlinear ionization… Processing with fs pulses transparent material objective and ‘microexplosion’ causes microscopic damage Processing with fs pulses transparent material objective translate sample Processing with fs pulses transparent material 100 fs objective 100 fs: laser energy transfered to electrons Processing with fs pulses transparent material objective 10 ps: energy transfer to ions Processing with fs pulses transparent material objective 100 ps: plasma expansion Processing with fs pulses transparent material objective 10–100 ns: shock propagation Processing with fs pulses transparent material objective 1 µs: thermal expansion Processing with fs pulses transparent material objective 1 ms: permanent structural damage Processing with fs pulses Points to keep in mind: fs laser processing works focusing very important no collateral damage Outline Processing with fs pulses Role of focusing Low-energy processing Role of focusing Dark-field scattering objective sample Role of focusing block probe beam… detector objective probe sample Role of focusing … bring in pump beam… detector pump objective probe sample Role of focusing … damage scatters probe beam detector pump objective probe sample Role of focusing 3 signal (a.u.) fused silica 0.1 µJ 2 1 0 –0.2 0 0.2 0.4 time (µs) 0.6 0.8 Role of focusing 3 signal (a.u.) fused silica 1.0 µJ 2 1 0 –0.2 0 0.2 0.4 time (µs) 0.6 0.8 Role of focusing vary numerical aperture in Corning 0211 threshold energy (nJ) 200 100 0 0 0.5 1.0 numerical aperture 1.5 Role of focusing spot size determined by numerical aperture: threshold energy (nJ) 200 Ith2 Eth IthA (NA) 2 and thus 100 Eth 2 Ith (NA) 2 0 0 0.5 1.0 numerical aperture 1.5 Role of focusing fit gives threshold intensity: Ith = 2.5 x 1017 W/m2 threshold energy (nJ) 200 100 0 0 0.5 1.0 numerical aperture 1.5 Role of focusing threshold energy (nJ) 6 5 4 100 0.6 0 0 0.5 1.0 numerical aperture 3 2 1.5 0.4 0.2 1 3 5 7 bandgap (eV) 9 11 threshold fluence (kJ/m2) threshold intensity (1017 W/m2) 200 Role of focusing 6 0.6 5 CaF2 4 3 0.4 fused silica 0211 2 0.2 SF11 1 3 5 7 bandgap (eV) 9 11 threshold fluence (kJ/m2) threshold intensity (1017 W/m2) vary material… Role of focusing 6 0.6 5 CaF2 4 3 0.4 fused silica 0211 2 0.2 SF11 1 3 5 7 bandgap (eV) 9 11 threshold fluence (kJ/m2) threshold intensity (1017 W/m2) threshold varies with bandgap Role of focusing Points to keep in mind: threshold critically dependent on NA surprisingly little material dependence avalanche ionization important Outline Processing with fs pulses Role of focusing Low-energy processing Low-energy processing threshold decreases with increasing numerical aperture threshold energy (nJ) 200 100 0 0 0.5 1.0 numerical aperture 1.5 Low-energy processing less than 10 nJ at high numerical aperture! threshold energy (nJ) 200 100 0 0 0.5 1.0 numerical aperture 1.5 Low-energy processing amplified laser: 1 kHz, 1 mJ 1 ms 100 fs heat diffusion time: diff ≈ 1 µs Low-energy processing long cavity oscillator: 25 MHz, 25 nJ 40 ns 30 fs heat diffusion time: diff ≈ 1 µs Low-energy processing 10 µm Low-energy processing high repetition-rate micromachining: structural changes exceed focal volume spherical structures density change caused by melting Low-energy processing transparent material objective cumulative energy deposition Low-energy processing transparent material objective cumulative energy deposition Low-energy processing transparent material objective cumulative energy deposition Low-energy processing transparent material objective cumulative energy deposition Low-energy processing 102 50 µm Low-energy processing 102 103 50 µm Low-energy processing 102 103 50 µm 104 Low-energy processing 102 103 50 µm 104 105 Low-energy processing radius (µm) 12 8 4 0 1 10 102 103 number of shots 104 105 Low-energy processing amplified laser 1 ms repetitive oscillator 40 ns cumulative Low-energy processing number of pulses repetition-rate dependence 102 103 104 105 0.1 1 repetition rate (MHz) As2S3, 100 fs, 7 nJ 10 Low-energy processing number of pulses repetition-rate dependence 102 103 104 105 0.1 1 repetition rate (MHz) As2S3, 100 fs, 7 nJ 10 Low-energy processing number of pulses repetition-rate dependence 102 103 104 105 0.1 1 repetition rate (MHz) As2S3, 100 fs, 7 nJ 10 Low-energy processing repetition-rate dependence 8 radius (µm) 6 N 105 104 103 102 4 2 0 0.1 1 10 repetition rate (MHz) As2S3, 100 fs, 7 nJ 100 Low-energy processing waveguide machining Low-energy processing waveguide machining Low-energy processing waveguide mode analysis CCD He:Ne Low-energy processing refractive index profiles and near field mode at 633 nm � ���� 1.518 n 1.516 1.514 1.512 –20 –10 Sagitta, Inc. 0 x (�m) 10 20 Low-energy processing refractive index profiles and near field mode at 633 nm �� ���� 1.518 n 1.516 1.514 1.512 –20 –10 Sagitta, Inc. 0 x (�m) 10 20 Low-energy processing refractive index profiles and near field mode at 633 nm �� ���� 1.518 n 1.516 1.514 1.512 –20 –10 Sagitta, Inc. 0 x (�m) 10 20 Low-energy processing 3D wave splitter 3 3 2 1 1 2 output 1 2 3 He:Ne Low-energy processing Bragg grating nλ Low-energy processing Bragg grating λ1 λ2 λ3 λ4 λ5 Low-energy processing monolithic amplifier laser active glass Low-energy processing Low-energy processing standard biochemical tools: species selective fs laser nanosurgery: site specific Nanoneurosurgery Caenorhabditis Elegans Juergen Berger & Ralph Sommer Max-Planck Institute for Developmental Biology Nanoneurosurgery Caenorhabditis Elegans simple model organism Nanoneurosurgery Caenorhabditis Elegans simple model organism similarities to higher organism Nanoneurosurgery Caenorhabditis Elegans simple model organism similarities to higher organism genome fully sequenced Nanoneurosurgery Caenorhabditis Elegans simple model organism similarities to higher organism genome fully sequenced easy to handle Nanoneurosurgery Caenorhabditis Elegans 80 µm x 1 mm Nanoneurosurgery Caenorhabditis Elegans 80 µm x 1 mm about 1300 cells Nanoneurosurgery Caenorhabditis Elegans 80 µm x 1 mm about 1300 cells 302 neurons Nanoneurosurgery Caenorhabditis Elegans 80 µm x 1 mm about 1300 cells 302 neurons invariant wiring diagram Nanoneurosurgery Caenorhabditis Elegans 80 µm x 1 mm about 1300 cells 302 neurons invariant wiring diagram neuronal system completely encodes behavior Nanoneurosurgery Caenorhabditis Elegans Nanoneurosurgery Caenorhabditis Elegans Bob Goldstein, UNC Chapel Hill Nanoneurosurgery Caenorhabditis Elegans Nanoneurosurgery Nanoneurosurgery ASH neurons responsible for osmotic avoidance ciliary projections extend through skin one on each side Nanoneurosurgery make ASH neurons express GFP GFP gene GFP … a b c ASH neuron gene d … Nanoneurosurgery GFP: absorbs UV, emits green Nanoneurosurgery cutting an axon Nanoneurosurgery cutting an axon Nanoneurosurgery pearling instability Conclusion wiring optoelectronics circuits of the future manipulating the machinery of life Summary important parameters focusing energy repetition rate nearly material-independent! Summary E (nJ) SINGLE-SHOT DISRUPTION CUMULATIVE EFFECTS 1000 basic science 100 data storage 3 2 1 10 1 2 3 He:Ne cell manipulation device fabrication 1 rep rate (MHz) SLIDE HEADING Funding: National Science Foundation Harvard Office of Technology and Trademark Licensing Acknowledgments: Prof. Nico Bloembergen (Harvard University) Willie Leight (Yale University) Yossi Chai (Sagitta, Inc.) For a copy of this talk and additional information, see: http://mazur-www.harvard.edu Processing with fs pulses 5 x 5 µm array fused silica, 0.65 NA 0.5 µJ, 100 fs, 800 nm Opt. Lett. 21, 2023 (1996) Processing with fs pulses microstructure scribed sample Processing with fs pulses microstructure scribed sample Processing with fs pulses fracture along scribe line Processing with fs pulses 1 µm Corning 0211 1.4 NA, 140 nJ