Liquid nanodispensing Thierry Ondarçuhu, Laure Fabié, Erik Dujardin, Aiping Fang Nanosciences group, CEMES-CNRS, Toulouse (France) Nanopatterning, molecule deposition Dynamics of liquids at sub-micron scale
Liquid volumes 10-6 l 10-9 l 10-12 l 10-15 l 10-18 l 10-21 l 1 μl 1 nl 1 pl 1 fl 1 al 1 zl 1 mm 100 μm 10 μm 1 μm 100 nm 10 nm
Molecules deposition? 500 nm JP Cleuziou, W. Wernsdorfer, V. Bouchiat, T.O., M. Monthioux, Nature Nanotech 2007 Deposited volume : towards single molecule (100 nm) 3 = 1 attoliter (10-18 l) of 1µM solution ~ 1 solute molecule Positioning on nanostructures
Direct patterning : liquid lithography Pipettes Pins ArrayIt D. Klenermann et al., Angew. Chem. Int. Ed. 2005 Ionscope Ltd BioPlume (LAAS, Toulouse) BioForce Nanosciences, Inc Ink-jet Park et al., Nature Mat. 2008
Dip pen nanolithography Review : Salaita et al. Nature Nanotechn. 2007 Piner, R. D. Science 1999, NanoInk, Inc Massive parallelisation
Methods Liquid lithography Pin and Ring method (DNA chips) ~ 200 µm Ink jet De Gan et al., Adv Mat 2004 1 µm Microlever plotters Belaubre et al., APL 2003 Few µm + Versatile -- Ø ~ 1 to 200 µm Dip pen lithography Piner et al., Science 1999 Hong, Mirkin, Science 2000 + Ø~ 10 nm -- Limits in terms of transferrable molecules -- No reservoir
NADIS : liquid NAno DISpensing Meister et al, Appl. Phys. Lett. 2004 A. Fang, E. Dujardin, T.O., NanoLett 2006
Fabrication of NADIS tips by focused ions beam (FIB) 2 steps : (i) Thinning of tip wall from the top (ii) milling at tip apex from tip side (record : 35 nm) 1 2 35 nm 100 nm 100 nm 251 nm 500 nm Surface functionalization Intact smooth gold surface (for thiolate chemistry) Smooth Si 3 N 4 surface for silane chemistry
Deposition procedure Liquid Glycerol ou glycerol-water mixtures (dilution max 6:4) Solutions of molecules, dendrimers, proteines, nanoparticules Loading of reservoir 10µm 10µm 10µm Droplet deposited with a micropipette and micromanipulator
Deposition procedure AFM Multimode Picoforce in force curve mode Imaging of molecules spots Force curve
Influence of substrate properties Hydrophilic tip with 400 nm aperture On hydrophilic SiO 2 On NH 2 -treated SiO 2 (θ av = 53 ) 1 µm On CF 3 -treated SiO 2 (θ av = 105 )
Ultimate dimensions : hydrophobic tips Hydrophobic tips (functionalized by dodecanethiol) 70 nm * 120 nm 35 nm Ø ~ 250 nm Ø ~ 75 nm Spot diameter ~ 2x aperture diameter 3.0µm 500nm A. Fang, E. Dujardin, T.O., NanoLett (2006)
Intermediate sizes Mixed tips 800 nm Gold removed Ø ~ 750 nm 1,2 µm 1.0 µm Spot diameter ~ size of hydrophilic region
Patterning of nanoparticles and proteins DsRed proteins 25 nm PS NPs 250nm 1 µm 3 µm EGFP proteins 1 µm
Comparison with other liquid dispensing methods 1 μl 1 nl 1 pl 1 fl 1 al 1 zl 1 mm 100 μm 10 μm 1 μm 100 nm 10 nm
Deposition set-up Set-up with two AFM tips Ondarçuhu et al., Rev. Sci. Instr. 2000
Deposition set-up Automated deposition Nanopositioning at a predefined place 570nm 2- Droplet deposited on electrodes 1- Reference droplets 1.6µm Position accuracy : Δx, Δy ~ 100 nm 300 nm M. Ben Ali. T.O., Langmuir. 2002
Limitation Evaporation of the open reservoir Cantilevers with integrated microfluidic channel Ex : NanoFountain pen Deladi et al., J. Micromech. Microengin. 2005 Kim et al., Small 2005 FluidFM Meister et al., NanoLett 2009
Liquid transfer mechanism Flow in nanochannel Spreading on surface Spreading dynamics Capillary force
Writing lines 5 µm 0,25 t = w/v Dynamics of spreading at sub-micron and millisecond scales
Interpretation Dynamics of spreading : Cox-Voinov equation 3 3 θ = θ m + 9. Vη / γ.ln( L s ) Spreading at constant volume (θ m =0) : Tanner s law θ 1 / R 3 1 / R 9 dr dt 1/10 R t Spreading at constant pressure 10 h θ Approximations : 2 D Pressure = 0 straight interfaces θm=0 θ h R R Small angles 0 1 0,0001 0,001 0,01 0,1 1 10 R R 0 1 /( 3 dr R R ) 1/ 4 0 R R 0 t dt 0,1
Real-time information Capillary force during nanodispensing
Interpretation of retraction force curves F (nn) 20 10 0-10 -20-30 -40-50 -60-70 z (nm) 0 100 200 300 400 500 600 Small aperture Hydrophobic tip Hydrophilic tip Profile of retraction force curves Correlation force curve shape - drop size Liquid transfer mechanism Realtime monitoring of deposit
Modelization with surface evolver http://www.susqu.edu/brakke/evolver/evolver.html Energy minimization for différent boundary conditions and constraints Pressure or volume Radius or contact angle Surface shape Energy Pressure Volume Force
Hydrophilic NADIS tips Large apertures (400 nm) Constant P defined by réservoir Small apertures (35 nm) Constant V No liquid flow during retraction 40 10 F (nn) 20 0-20 -40-60 -80 z (nm) 0 100 200 300 400 500 Rsurf = 400 nm, Rtip = 300 nm P = 1.4 10 4 Pa Exp Calc F (nn) 0-10 -20-30 -40 z (nm) 0 20 40 60 80 100 Exp Calc Rsurf = Rtip = 37.5 nm V = 0.4 al Q Q Poiseuille Nadis 10 L. Fabié, H. Durou, T.O., Langmuir, 2010 Q Q Poiseuille Nadis 0,12
Correlation between droplet size and force curve Hydrophilic tip Zrupt Rsurf Rsurf F (nn) 20 10 0-10 -20-30 -40-50 -60-70 z (nm) 0 100 200 300 400 500 600 4.4µm 500 Z rupt (nm) 400 300 200 Direct correlation between force curve and deposit size 100 Rtip = 250 nm 0 0 200 400 600 R 800 surf (nm)
Evaporation of femto-droplets Mass sensing device (picogramme) J. Arcamone, et al., J.Phys.Chem B (2007) Droplet dispensing by NADIS Litterature : «microdroplets» in volume (1µl = 1 mm 3 ) This study : «femtodroplets» (1µm 3 = 1 fl) 10 9
Conclusion NADIS : manipulation of liquid at sub-micron scale Patterning method Towards single molecule deposition Nanopositioning on predefined structures Tool for studying liquid dynamics at sub-micron scale Spreading dynamics Nanomechanics of meniscus Evaporation of femtodroplets