Emerging new non conventional tools

Transcription

1 Emerging new non conventional tools

2 Near field lithography

3 Near field lithography

4 Near field lithography through local electrochemistry example of gold a) Surface water condensation b) Monolayer of oxidized gold H 2 O Gold surface oxygen atoms gold atoms c) Exchange process d) Dissolution of gold atoms

5 examples (ex L2M): LPN

6 Near field scheme Lithography mode Electrical pulse Mechanical pressure Threshold Below threshold Observation/alignment

7 Local CVD deposition PF 3 PF 3 Rh Cl Cl Rh PF 3 PF 3 de-passivation deposit low pressure one pulse one atom 100nm GPEC Marseille

8 Example of useful structures Anodization of GaAs Anodization of Nb ETH Zürich CRTBT Grenoble

9 Use carbon nanotube to improve the resolution Vibrations problem: needs for short tube y 0.2µm LEPES Grenoble

10 Si-H depassivation UHV-STM IEMN Lille

11 CEA Saclay

12 Magnetic nanoconstrictions Défauts naturels ou artificiels Matrice 10*10 Bain électrolytique Isolant Ferromagnétique Substrat Défaut (lpm, lsf) Caractérisation électrique 200 nm Boule Constriction K. Bouzehouane et al, Nano Lett. 3(11), 1599 (2003) UCL Louvain, UMR CNRS- Thales Orsay

13 Field emission lithography

14 Results on resist, resolution about 40nm (forward scattering) Stanford Univ.

15 Slow process parallel set-up

16 Thermal lithography Millipede project IBM Zürich

17 Dip pen lithography Application to DNA Chip resolution =40nm Northwestern Univ.

18 Alternative lithography

19 Nano-imprint lithography (NIL) 1.temp +pressure 50Bars resist mold substrate 2. cooling 3. Remove mold (tricky!) 4. Etch of residual resist Slow process, needs masks at 1/1 scale i.e. e-beam lithography Resolution demonstrated down to 10nm. Very chip! LPN

20 examples LPN

21 Trilayer Nanoimprint Lithography --> tri-layer technique for improved aspect ratio - better CD control - non-planar surfaces PMMA or hybrane Ge 1. Imprint of top polymer layer PMGI layer thermostable at Tg of PMMA and hybrane 2. Transfer in PMGI Array of nanoholes in hybrane layer (80 nm) Dot array 150 nm diameter (60 nm Ni) 3. Lift-off Ni Y.Chen et al. Eur. Phys. J. Appl. Phys. 12,223 (2000) SiO 2 /Si nanopillars height 500 nm LPN

22 NIL : resolution and applications 60 nm period 100 nm period Metal nanodot arrays duplicated by nano-imprint and lift-off Fresnel zone plate for X-ray focusing Magnetic micro-rings SiO2 nanopillar array LPN

23 Nano-embossing Si wafer Polymer pellets Patterned Si mold Compression (T>Tg) Separation (T<Tg) Thermal bonding The polymer pellets are pressed directly into the silicon mold Extremely short processing time Excellent reproducibility V. Studer, A. Pépin, Y.Chen, Appl. Phys. Lett. 80, 3614 (2002) LPN

24 Nano-embossing with PMMA pellets T g = 108 C T emb = 180 C, P~ 50 bar, t~ 10 min 10µm-deep channel 10 µm 100µm 1µm - excellent shape definition, and surface quality (<10nm surface roughness) - possible to mold both micro- and nanostructures of different depths simultaneously - other thermoplastic polymers under study (Topas COC, PC, etc. ) LPN

25 Soft Lithography Single layer Micro-contact printing Bi-layer 1. Fabrication du moule 1. Inking (PDMS stamp) PDMS A:B 1:20 1:5 Moule 2. Printing 2. PDMS coulé sur moule Au PMMA 3. Réticulation du PDMS 3. Self-assembling 4. Séparation 4. Etching Y.N. Xia, G.M. Whitesides. Angew. Chem. (1998) head Hydrocarbon S.R. Quake et al. Science (2000) Sulfur Au Substrate Self-assembled thiol/thioether monolayer

26 Tri-layer Micro Contact Printing 1. Inking (PDMS stamp) Au Co 2. Printing Au PMMA 3. Self-assembling 4. Etching head Hydrocarbon Sulfur Au Substrate Self-assembled thiol/thioether monolayer S.P. Li et al. J. Mag.Mag. Mat. 241, 447 (2002) Use of molecular adhesion Example : thiol group on gold LPN

27 Fluid penetration and DNA confinement 500 µm Application: electrophoretic separation of DNA molecules in a nanostructured artificial gel λ DNA strand (48 kbp) tagged with YOYO-1 fluorescent dye entering a 200 nm-wide x 80nm-deep channel (normal stretching 17µm) 1 mm solution of fluorescein penetrating inside a nanopillar array connected to a 50µm x 10µm channel LPN

28 Mammalian cell sorter collaboration J.P. Thiery (Institut Curie) V. Studer, R. Jameson, E. Pellereau, A. Pépin et Y. Chen (MNE 2003) LPN

29 UV assisted imprint Quartz mold substrate UV radiation UV hardening of the resist Much faster, still problem for alignment, commercial systems now

30 Conclusion on lithography techniques Technique Resolution Use Remarks contact 0.25mm Labs and R&D Economical Optical lithography proximity 2mm Labs and R&D projection 80nm Industrial Economical but weak resolution Expensive but with constant progress EUV <50nm Industrial May be the next technique for 2005 Electron beam lithography 1nm Labs and R&D Fabrication of optical masks Technique without mask best resolution Ion beam lithography 8nm Labs and R&D Better for etching than lithography (diagnostic) Near field lithography Atom 10nm Labs Economical, very slow specific Nanoimprint & co. 10nm Labs and industry? Economical, fast Alignment problems mask 1 :1