1. Insect-inspired capillary nanostamping (IICN)
Martin Steinhart
AIM: establishing IICN as next-generation contact lithography
for massively parallel high-throughput printing
of dense large-scale arrays of discrete tailor-made nanostructures

2. Animal adhesion by contact splitting
Animals adhere to ceilings via fibrillar adhesive pads forming many discrete contact points
Advantages:
Reliable contact formation to rough counterpart surfaces
Strong but highly reversible adhesion
High durability of pads
Restricted crack propagation
S. N. Gorb, M. Sinha, A. Peressadko, K. A. Daltorio, R. D. Quinn, Bioinsp. Biomim. 2007, 2, S117

3. Insect adhesion: contact splitting + wet adhesion
Wet adhesion: enhanced adhesion by ejection of adhesive secretion through pores in fibrillar contact elements
Eisner, Aneshansley, PNAS 2000, 97, 6568
50 µm
50 µm
Fibrillar adhesive pad
Footprint of fibrillar adhesive pad
Abraded fibrils of adhesive pad with pores (Geiselhardt et al., J. Comp. Physiol. A 2010, 196, 369)

4. IICN: transferring wet insect adhesion principles to contact lithography
Continuous ink supply via porous stamp to large-scale array of nanoscale dispensing elements
Xue, Steinhart, Gorb et al.; Nano Lett. 2013, 13, 5541; Nat. Commun. in revision

5. IICN: transferring wet insect adhesion principles to contact lithography
Continuous ink supply via porous stamp to large-scale array of nanoscale dispensing elements
Ink deposition via capillary bridges between dispensing elements and printed surface
Xue, Steinhart, Gorb et al.; Nano Lett. 2013, 13, 5541; Nat. Commun. in revision

6. IICN: transferring wet insect adhesion principles to contact lithography
Continuous ink supply via porous stamp to large-scale array of nanoscale dispensing elements
Ink deposition via capillary bridges between dispensing elements and printed surface
Massively parallel liquid-bridge templated formation of sub-attoliter nanostructures on printed surface
Xue, Steinhart, Gorb et al.; Nano Lett. 2013, 13, 5541; Nat. Commun. in revision

7. Why IICN?
Massively parallel, large-scale generation of arrays of discrete tailor-made nanostructures
Flexible, liquid bridge-templated generation of diverse types of nanostructures (encapsulated nanocontainers, nanorods,…)
High throughput by short cycle times
NO time-consuming self-organization of templates
NO use of sacrificial templates

8.  x  Why IICN? IICN Classical contact lithography
Scanning probe lithography
Block copolymer lithography
Large areas  x
Short cycle times
Printing on surfaces submerged in liquid 
Generation of nanorod arrays
No self-assembly of templates
No use of sacrificial templates

9. Limitations of state-of-the-art methods for lithographic transfer of functional materials
State-of-the-art contact lithography
Only transfer of thin adsorbed layers
Mechanical limitations of stamp design
Long cycle times
(time-consuming re-inking after printing)
Scanning probe lithography
Slow serial pixel-by-pixel method
Only small areas can be patterned
Block copolymer (BCP) lithography
Time-consuming self-organization of BCP templates
BCPs are destroyed (sacrificial templates)
Destruction of BCPs: additional process step; sample contami-nation possible

10. Technical design of IICN de-vices & design of IICN stamps
Upscaling &
technology transfer
Method development
Model applications
Technical design of IICN de-vices & design of IICN stamps
IICN operational modes
Liquid-on-solid IICN
High-temperature IICN (T ≤ 250°C)
Electromodulated IICN
Liquid-in-liquid IICN
Alternative stamp topographies

11. Upscaling &
technology transfer
Method development
Model applications
“Nearly-ergodic” lab-on-chip con-figurations with potential single-molecule resolu-tion (b2.5+b2.6)
Massively parallel liquid bridge-guided formation of nanorod arrays (b2.1)
Ordered nanospot and nanorod arrays + ordered porous membranes by IICN nanodroplet lithography (b2.2 - b2.4)

12. Upscaling &
technology transfer
Method development
Model applications
Upscaling IICN as next generation contact lithography:
Continuous roller process
Basic patent covering method, device configurations, printing products and applications filed to German Patent Office
Perspectives: licensing or start-up company

13. Ultrathin nanoporous carbon membranes by nanodroplet lithography
This PhD project (I):
Ultrathin nanoporous carbon membranes by nanodroplet lithography

14. Ultrathin ordered nanoporous membranes by IICN nanodroplet lithography
Depostion of nano-droplet arrays by IICN for use as shadow mask

15. Ultrathin ordered nanoporous membranes by IICN nanodroplet lithography
Depostion of nano-droplet arrays by IICN for use as shadow mask
Depostion of aromatic self-assembled monolayer on areas not protected by IICN nanodroplets

16. Ultrathin ordered nanoporous membranes by IICN nanodroplet lithography
Depostion of nano-droplet arrays by IICN for use as shadow mask
Depostion of aromatic self-assembled monolayer on areas not protected by IICN nanospots
Cross-linking of SAM layer and lift-off
 ultrathin nanoporous membranes with pores at positions of IICN nanospots

17. Applications & performance tests
- Size-selective separation performance of supported polymerized SAMs will be tested with fluorescent nanoparticles.
- Single-component permselectivity controlled by electrochemical potentials regulating the surface charges of graphitized nanoporous SAM membranes will be tested with dyes such as anilinium chloride, rhodamine B, and methyl viologen as function of ionic strength, pH and temperature.
- Electrochemically modulated ion-transport selectivity will be tested by mixtures of carboxylic acids and basic amines as well as by mixtures of monocarboxylic, bicarboxylic and tricarboxylic acids.

18. Self-ordered nanoporous alumina membranes by nanodroplet lithography
This PhD project (II):
Self-ordered nanoporous alumina membranes by nanodroplet lithography

19. Self-ordered anodic aluminum oxide (AAO)
Self-ordered hexagonal arrays of aligned cylindrical pores with sharp pore diameter distribution: stable, highly ordered porous membranes for
separation
heterogeneous catalysis
preparation of nanorod arrays by replication molding
H. Masuda, K. Fukuda, Science 1995, 268, 1466

20. IICN-supported production of ordered nanoporous alumina membranes
Problems:
Production by anodization of aluminum involves three tedious anodization/etching steps in acidic solutions
Arrangement of pores by tedious self-assembly process

21. IICN-supported production of ordered nanoporous alumina membranes
Aims: replacing
2 out of 3 tedious anodization/etching steps in acidic solutions and
pore arrangement by tedious self-assembly
by IICN to save energy, to reduce use of acidic solutions and to enhance throughput

22. Classical production of ordered nanoporous alumina membranes (H
Classical production of ordered nanoporous alumina membranes (H. Masuda, K. Fukuda, Science 1995, 268, 1466) + _
Aluminum

23. First step: anodization in acid yields sacrificial Al2O3 layer in which growing pores self-assemble
surface
250 nm
underside + _

24. To be replaced by IICN _ +
First step: anodization in acid yields sacrificial Al2O3 layer in which growing pores self-assemble
surface
250 nm
underside + _
To be replaced by IICN

25. First step: anodization in acid yields sacrificial Al2O3 layer in which growing pores self-assemble
surface
250 nm
underside + _

26. Wet etching of sacrificial self-ordered nanoporous AAO layer yields Al surface with indentations replicating pore bottoms + _

27. To be replaced by IICN _ +
Wet etching of sacrificial self-ordered nanoporous AAO layer yields Al surface with indentations replicating pore bottoms + _
To be replaced by IICN

28. Aim: Al substrates with patterns guiding pore growth by IICN+ _

29. Second anodization yields ordered porous membrane; pore growth templated by indentations+ _

30. Etching of pore array reproducing ordering of IICN stamp
Perspective: IICN-supported production of ordered nanoporous alumina membranes
Massively parallel IICN stamping of extended arrays of corrosive ink nanodroplet arrays
Massively parallel generation of etch pitches at droplet positions as seeds for growing pores
Etching of pore array reproducing ordering of IICN stamp

31. Etching of pore array reproducing ordering of IICN stamp
Perspective: IICN-supported production of ordered nanoporous alumina membranes
Massively parallel IICN stamping of extended arrays of corrosive ink nanodroplet arrays
Massively parallel generation of etch pitches at droplet positions as seeds for growing pores
Etching of pore array reproducing ordering of IICN stamp

32. Etching of pore array reproducing ordering of IICN stamp
Perspective: IICN-supported production of ordered nanoporous alumina membranes
Massively parallel IICN stamping of extended arrays of corrosive ink nanodroplet arrays
Massively parallel generation of etch pitches at droplet positions as seeds for growing pores
Etching of pore array reproducing ordering of IICN stamp

33. Principal Investigator: Martin Steinhart
Institute of Chemistry of New Materials
University of Osnabrück
ResearcherID: B
ORCID identifier