Nanotechnology is a rapidly growing area of research and development (R&D) focussing on materials and structures with sub-microscale dimensions. The nanoscale can be difficult to visualize given that is a couple of orders of magnitude below anything that is visible with the human eye.
A single nanometre (nm) is one-billionth of a meter (10-9), and the nanoscale roughly encompasses any structure ranging from 1 – 100 nm. Even compound microscopes are incapable of resolving features with dimensions of less than 200 nanometres (nm). Conducting research or developing products within the remit of nanotechnology requires absolute precision and high-purity materials. Gold-coated substrates and surfaces satisfy both these requirements. At Platypus Technologies, we offer gold-coated products for analysis and characterisation of materials (on the nano, micro, or macro-scale) via specific analytical techniques.
How are Gold-Coated Substrates Made? Electron beam physical vapor deposition (EBPVD) is one of many enabling tools used to produce critical components for nanotechnology. It is routinely employed to generate high-purity thin films on functional substrates for a diverse application range. This is the method we use at Platypus Technologies to generate high-purity gold-coated substrates.
The process involves a target anode comprised of 99.999% pure gold and a substrate, typically mica glass or silicon. A tungsten-based electron beam bombards the target and converts the solid gold into a gaseous phase, which travels via line of sight to deposit upon the surface of the substrate. The result is a functional substrate coated with a very thin layer of gold, typically in the region of 10 nm and up.
Uses of Gold-Coated Surfaces
Gold is a readily-functionalized material that is inherently resistant to oxidation and chemically inert. It also makes for an excellent conductor of electricity. At Platypus Technologies, we develop EBPVD gold-coated glass and silicon wafers for a choice of end-use applications from product development to materials science. Our microscope slides and coverslips are ideal for life science research and reflectivity analysis, while our silicon wafers and template stripped gold chips are used in a range of research applications, from atomic force microscopy (AFM) and scanning electron microscopy (SEM) to sensor development.
People use a gold-coated substrate because they need to do some type of characterization in a material they are studying. The type of characterization depends on the specific question, but it typically involves one of the following techniques:
- Atomic Force Microscopy
- Scanning Tunnelling Microscopy
- Scanning Electron Microscopy
- Fluorescence Microscopy
- Infrared (IR) spectroscopy
- Raman spectroscopy
- Surface Plasmon Resonance (SPR)
- Cyclic Voltametry
- Electrochemical Impedance Spectroscopy
Each gold-coated product serves a different technique. For example, glass with 50-nm gold film is used for SPR. Take a look at our individual product pages to find more about specific applications.
Advantages of Platypus Tech Gold Films
Other manufacturers develop gold coatings via thermal vapor deposition or sputtering, but we rely on EBPVD because of our expertise and precision in this area. By oxygen plasma cleaning our substrates prior to deposition, we ensure maximum adhesion and promote cleanliness in the finished part. We can also impart a titanium adhesion layer to ensure maximum bonding between the gold thin film and the substrate, thus promoting uniformity.