| Low Dimensional NanoStructures |
 |
Our group is developing novel synthesis routes for low dimensional nanostructures & nanomaterials using state of the art deposition techniques and their combinations: atomic layer deposition, physical vapour deposition, and local focused electron and ion beam induced chemical vapour deposition. Our R&D activities are driven by finding novel nanostructured materials for sustainable energy technology, nanotechnology, and health issues. Special focus is given to the development of:
i) Non-conventional nanodevice prototyping: using and developing our state-of-the art, minimally invasive, maskless, resistless, direct write focused electron/ion beam technique allows us to locally add or remove functional nanomaterial at nanometer scale to refine, functionalize, or prototype sensors, telecom lasers, or scanning probe tips individually at will in a single-step post-process step.
ii) Functionalization of non-planar substrate architectures: developing low-temperature ALD for conformal coatings of high-aspect ratio, non-planar substrate architectures, like nanowire or nanotube carpets, perforated membranes, or polystyrene beads.
iii) Development of novel low dimensional nanomaterials: using and developing sequential and co-evaporation concepts for PVD, ALD, and FEB/FIB assisted CVD for thin multilayer films, nano-composites, core-shell structures, and nanowires.
iv) Development of SEM integrated characterization tools: composition, shape, mechanical and electrical properties, gas injection systems.
|
 |
| Minimally invasive nanomaterial synthesis with local focused electron and ion beam induced chemistry |
 |
 |
| Minimally invasive FEBIP & FIBIP examples. |
|  | Gas assisted Focused Electron/Ion Beam Induced Processing (also known under the acronyms FEBIP and FIBIP) constitutes a non-conventional rapid prototyping platform which allows for synthesis (deposition and etching) of conventional and novel materials for nanodevices. We investigate a) the underlying key physico-chemical processes to gain compositional and shape control over the process, b) the synthesized novel granular and nanocomposite material with respect to electrical, magnetical, mechanical, and op-tical properties using specifically developed SEM-integrated meas-urement setups, c) develop nanodevice prototypes, like magnetic bead sensors, polarization gratings for telecom lasers, and tip en-hanced Raman spectroscopy. |
 |
 |
| ISBN13: 9780199734214 ISBN10: 0199734216 Hardback, 840 pages |
|  | Highlight: I. Utke and A. Goelzhaeuser, Small, Minimally Invasive, Direct: Electrons Induce Local Reactions of Adsorbed Functional Molecules on the Nanoscale, Angew. Chem. Intl. Ed. 49(49) (2010) 9328, DOI: 10.1002/anie.201002677. Featured: M. Gabureac et al., Granular Co-C nano-Hall sensors by focused-beam-induced deposition, Nanotechnology 21 (11) (2010) 115503, DOI: 10.1088/0957-4484/21/11/115503.
M. Jenke et al., Toward Local Growth of Individual Nanowires on Three-Dimensional Microstructures by Using a Minimally Invasive Catalyst Templating Method, Nanoletters 11(10) (2011) 4213, DOI: 10.1021/nl2021448.
L. Bernau et al. Tunable Nanosynthesis of Composite Materials by Electron-Impact Reaction, Angew. Chem. Intl. Ed. 49 (47) (2010) 8880, DOI: 10.1002/anie.201004220.
Review: I. Utke, P. Hoffmann and J. Melngailis, Gas Assisted fo-cused electron beam and ion beam processing and fabrication, J. Vac. Sci. Technol. B 26 (2008) 1198-1276.
Contact: Ivo Utke
|
 |
| SEM add on Developments |
 |
 |
| Compact GIS for low vapour pressure molecules. |
|  | GIS in SEM Our Group develops gas injection systems and software for gas distri-butions. The GIS Simulator program is a three-dimensional implementation of the test-particle Monte Carlo method for rarefied gas flow through a circular tube which connects a large vessel containing the gas and a vacuum chamber. It predicts the gas flux distribution which impinges on the substrate when exiting the circular tube. Different tube exit ge-ometries can be chosen: straight, bevelled with FEB/FIB access hole, doubly perforated closed tube, conical tube. The simulations were verified against experimentally measured flux distributions. Related papers: V. Friedli and I. Utke, Optimized molecule supply from nozzle-based gas injection systems for focused electron- and ion-beam induced deposition and etching: simulation and experiment. J. Phys. D: Appl. Phys. 42 (2009) 125305 (11pp), doi:10.1088/0022-3727/42/12/125305
|
 |
 |
| FIBSIMS. The AFM in SEM to measure crater roughness is not shown. |
|  | FIBSIMS The focus of our TOFSIMS development work has been on a relative-ly low-cost versatile instrumentation module intended as an add-on to a standard high vacuum FIB chamber. Orthogonal extraction provides a high effective duty cycle and avoids the need to pulse the primary beam or to use monoisotopic gallium, thus no changes to the FIB hardware are necessary. When SIMS measurements are not required, the front part of the extraction ion optics simply clips off, thus allow-ing the full range of sample sizes to be used by the FIB. The prototype instrument has useful ion yields while depth profiling with 20 keV gallium primary ions and also chemical images with lateral resolutions of better than 40 nm are easily achieved.
J.A. Whitby et al. High Spatial Resolution Time-of-Flight Secondary Ion Mass Spectrometry for the Masses: A Novel Orthogonal ToF FIB-SIMS Instrument with In Situ AFM Adv. Mat. Sci. Engin. 2012 (1012) 180437, DOI: 10.1155/2012/180437. Contact: James Whitby, Ivo Utke
|
 |
 |
| Nanopillar vibration test |
|  | Related book chapter: V.Friedli et al. AFM Sensors in Scanning Electron and Ion Microscopes: Tools for Nanomechanics, Nano-analytics, and Nanofabrication, Applied Scanning Probe Methods VIII, Eds. B. Bushan, H. Fuchs, M. Tomitori, Springer 2008, Series: NanoScience and Technology (www.springer.com/978-3-540-74079-7). V. Friedli, I. Utke, K. Mølhave and J. Michler, Dose and energy de-pendence of mechanical properties of focused electron-beam-induced pillar deposits from Cu(C5HF6O2)2. Nanotechnology 20 (2009) 385304 (11pp), doi:10.1088/0957-4484/20/38/385304
|
 |
| Equipment/Service: |
 |
We operate a small grey room facility with electron beam and UV lithography. FIB and FEB are available for prototyping within research projects. Together with Alemnis, an Empa startup, we also offer solutions for gas injection systems which can be retrofitted to existing SEMs or Dual Beam machines. Our SEM add-ons can be operated on your specific samples.
SEM Hitachi S3600N (tungsten electron emitter) with XENOS lithography and ALEMNIS gas injection system and nanomanipulation: Dedicated variable pressure SEM for FEBIP chemistry development and classical e-beam lithography.
FIBSEM, Tescan Vela (W-emitter, Ga-ion source) with lithography and ALEMNIS gas injec-tion, nanmanipulation: for FIBIP, ion milling, FEBIP.
FIBSEM, Tescan Lyra3 (FEG, Ga-ion source) with e-beam/ion lithography and ALEMNIS gas injection system, FIBSIMS.
Residual Gas Analyser: Stanford Research System 300AMU.
RF Plasma Cleaning system, XEI: Evactron 24/25.
More SEM integrated setups: 4-point probing station, compression/indentation setups (10 mN, 1mN), nanomanipulations, nanopositioning systems, superparamagnetic bead detection system, AFM in SEM.
ALD reactor: lab-built reactor allowing for 2-3 inch wafers, 3 gas ports for nanolaminate film deposition, Labview control.
PVD Mantis: 1e-8 mbar, 3 magnetron sputter sources (1 RF), Mini-ebeam evaporator with 4 independent sources.£
In 2008 we organised the 2nd international FEBIP (focused electron beam induced pro-cessing) workshop at Thun with 90 international participants from more than 13 countries all over the world. |
 |
 |
| |
 |
|
|
 |
- Head of Laboratory
- Group Leader
- Ph.D students
|
|
|
|
 |
|
|
 |
|
|
 |
|