Nanoparticle production

Nanoparticles (NPS) are produced by a "terminated gas condensation" (TGC) method. In this technique, a DC magnetron is used to sputter target material. The sputtered atoms enter the high pressure condensation zone where their mean free path becomes very small and they quickly thermalize. Nanoparticles are formed as these thermalized atoms migrate towards the expansion zone.

The NPS generated by NanoGen50 source tend to posses one additional electronic charge and this allows them to be electrostatically manipulated either through deflection, focusing or acceleration. The acceleration towards the substrate allows the particle impact energy to be controlled precisely. At low acceleration (<<1eV per atom) the particles soft land without deformation. At higher energies they undergo a small degree of interface mixing and form a layer of bound nanoparticles. Such nanoparticle manipulation produces a variety of coating morphologies from nanoparticle powder, through porous films to crystalline structures.



Alloy nanoparticle production

In addition to growing compound nanoparticles such as oxides, hydrides and nitrides, it is possible to grow complex alloy nanoparticles. Our NanoGenTrio source has three independent coplanar targets, and by precisely controlling gas flow, a rapid mixing of atomic vapour from different targets can be achieved.

Core-shell nanoparticle production

Coreshell nanoparticle has a core of one material surrounded by a shell of another material. The composition of the core and shell can be varied and this presents an opportunity to create structures with combination of properties that neither individual material possesses.

When nanoshell coater is placed in-line with the nanoparticle source, the beam of nanoparticles enters the Nanoshell chamber, where it travels trough a vapour generated by a linear magnetron source and becomes coated with sputtered material. To ensure more efficient coating, the beam is collimated and decelerated by a series of electrostatic lenses. The resulting coreshell coated nanoparticles can be deposited on a substrate.



Filtering of nanoclusters by size

In addition to growing compound nanoparticles, it is possible to filter them by mass and size to produce size-selected nanoparticle coatings. Our MesoQ quadrupole mass filter is positioned at the nanocluster source exit, which allows precise manipulation of negatively charged nanoclusters.



TGC Method

Advantages of TGC method of nanoparticle production

TGC Chemical Synthesis
Nanoparticles are of semiconductor purity. No solvent or gas-based contaminants. Contamination problems.
Fast development cycle. Slow development cycle.
Close to 100% beam ionisation allows controlled acceleration => controlled adherence and density of nanoparticle films. Difficult to apply to surfaces.
The particle size may be designed over a wide range of sizes. Difficult to design particle size.
Controlled cluster stoichiometry.  
Powdered films to single crystal. One sort of nanoparticles.
Deposition onto plastic or other insulators.  
It is possible to make porous structures by semi-embedding nanoparticles followed by an etch process.  
Difficult to produce free nanoparticles. Good for bulk production in solution or powder form.