Nanomaterials

Nanotechnology and Nanomaterials Applications

Design and Manufacturing in the Nano World

Nanofabrication is the design and manufacturing of devices with dimensions measured in nanometers. To use the advantages of nanotechnology, you need to create small structures. Charged particles like ions or electrons are often your method of choice. The interaction between the ion or electron beam and the sample surface allows you to manipulate structures or properties of the surface. When used in combination with different gases, you are able to perform complex processes such as etching or material deposition. This enables creation of superior new materials and systems with complex mechanical, electronic, optical, magnetic or fluidic functions.

Nanofabrication, Patterning and Lithography

Todays and future applications require materials with improved electronic, magnetic, optical and mechanical properties. Many of these properties are defined by the structure and composition in the size range below 100 nm. Carl Zeiss is the only supplier that offers solutions for the fabrication of structures from the millimeter to the nanometer range. For the fabrication of sub-10 nm structures with high aspect ratios you use ORION NanoFab Multi-Ion Microscope. The advantage of this technology is that helium and neon ion beam lithography don’t exhibit proximity effects. You achieve uniform nested patterns without dose modification to account for proximity effects.

Nanophotonics, Plasmonics and Metamaterials

Metamaterials are a class of artificial materials, where the optical or magnetic properties are modified by changing the structure of the surface. Photonic crystal structures allow to improve the properties of optical devices. These are useful in all products for light transmission and optical measurement. The FIB patterning solution offers a powerful package to create these kind of structures. ORION NanoFab is your tool of choice for applications that require creation of plasmonic structures that exhibit surface or localized plasmon response at optical frequencies or higher frequency ranges.

Nanoparticles

Nanoparticles are of great importance in the field of catalysis or for modern nano-material applications. Your goal is usually a characterization of size, shape, chemical composition and distribution on a nm- or even sub-nm scale. You investigate the important features of your nanoparticles down to smallest sizes. ATLAS 3D allows large volume acquisition of your sample at highest resolution. This enables you to find specific nanoparticles within a polymer matrix and lets you analyse them.

Nanopores

Nanopores with diameters less than 10 nm are necessary for realization of advanced devices with applications in diverse areas. These include chemical sensing, DNA sequencing, biomolecule filtration, biomolecule sensing and X-ray holography. ORION NanoFab enables direct fabrication of nanopores with diameters as small as 4 nm and high aspect ratios of 10:1 or more.

Graphene Research

Graphene is a very promising next generation material. When made into specific shapes, you are able to modulate certain properties such as the bandgap. Graphene is a very delicate material because it is single atom thick and requires very gentle machining. Using the gentle and precise machining capability of ORION NanoFab, you create complex graphene devices with sub-10 nm features.

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Graphene is a tightly packed layer of carbon atoms that are bonded together in a hexagonal honeycomb lattice. Only one atom thick (335 pm) but up to several micrometers in lateral extent, graphene shows many extraordinary material properties. As an electric conductor, it performs as well as copper. In terms of its ability to transport heat, it outperforms all other known materials. Optically it is highly transparent but completely impermeable to any other atoms. Harder than steel and also showing a high elasticity, graphene unites several astonishing material properties. This makes graphene one of the most scientifically investigated and promising materials for technical applications. Use ZEISS instruments for your investigations, whether you need the nano-patterning performance of an Ion Beam microscope, a high end light microscope with customized modules or the power of a field emission scanning electron microscope for sensitive samples.

Monolayer, Bilayer, Multilayer Graphene

After the preparation of graphene with either exfoliation or a chemical vapor process (CVD), the number and quality of the produced graphene layers need to be checked. Measure the number of layers with the contact free and substrate independent module for Total Interference Contrast with ZEISS Axio Imager 2 and detect holes in continuous layers. Your graphene research application benets from ZEISS GeminiSEM 500 when you need high resolution images of a number of individual layers. Use its Energy selective Backscatter detector with its insensitivity to charging and acquire images of graphene at high resolution in a unique backscatter contrast. Determine the exact quantitative height with the in-situ AFM system.

Defects and Functional groups in Graphene

Before integration into a final device, defects in graphene are evaluated: carbon atoms can be sp3 -hybridized, functionalized, oxidized or missing. The chosen method here is Raman imaging, which, as a time consuming method, needs preselection of regions of interest. The in-situ Raman integrated into ZEISS GeminiSEM is the ideal tool for this purpose as the integration saves time in the workflow.

Integration in Electronic Devices

Graphene has the potential to enhance the performance of electronic devices such as transistors and super capacitors. This is achieved by band gaps in graphene which are produced by creating thin ribbons. The narrower the bands, the higher the band gap.  The desired width of a graphene ribbon is less than 20 nm. The ZEISS Ion Microscope ORION NanoFab allows mask-less, contact-free, direct writing of patterns in graphene using a focused helium ion beam.
The outstanding resolution of the ion beam allows nano-structuring of graphene in the sub-10 nm range.

Integration in LEDs

Graphene functions as conductive back and/or front contact in LEDs. After the chemical vapor deposition of graphene on a substrate, the different expansion coefficients lead to wrinkles in graphene layers. In addition residues of PMMA (Polymethy methacrylate) remain on the surface of graphene after a transfer process. This can be partly healed by an annealing step. The quality influences the homogeneity of distribution and height of the semiconductor rods grown on top. The quality of the graphene front contact is in turn dependent on the semiconductor growth. Investigate the thin graphene layer on top of the semiconductor rods with high surface sensitivity using ZEISS ORION NanoFab.

Integration in Isolations

High-performance heat insulations are needed to improve energy efficiency in buildings. Freeze-casting suspensions of cellulose nano-fibres, graphene oxide and magnesium silicate (sepiolite) nano-rods are used for the production of super-insulating, fire-retardant foams. They perform better than traditional polymer-based insulating materials, are lighter and exhibit high thermal conductivities that are about half of that of expanded polystyrene. Find out more about pore orientation and density by a 3D reconstruction of the foam’s tubular pore structure with the ZEISS X-ray microscope Xradia Versa.

Integration in Batteries

The low electrical conductivities of sulfur in lithium sulfur batteries can be improved by using graphene as current collector. The intermediate polysulfide products and the final Li2S product affect the utilization of the active sulfur material and the rate capability of the battery. Meanwhile graphene functions as a reservoir and thus the polysulfide can be reused.
The volume change between sulfur and Li2S during charge/discharge induces stress in the electrode due to the different densities. It destroys its structural stability, which leads to rapid capacity decay. A sandwich of graphene on both sides of the sulfur electrode accommodates the large volumetric expansion. Verify and quantify these processes with a ZEISS X-ray microsope Xradia Versa.