Nanoceramic is a unique dielectric material – a powerful electrical insulator that is also a good conductor of heat. The thermal properties of Nanoceramic make it ideal for use as an electrical barrier in thermally demanding applications, particularly LED applications such LED packaging, UV LED applications for curing printer inks and LED modules.
Nanoceramic is usually manufactured into large sheets similar to metal clad PCBs (MCPCBs) or insulated metal substrates (IMS) for the PCB market or smaller tiles with thin film circuitisation for the semiconductor market. It is also possible to convert the surface of complex 3D shapes to a Nanoceramic, enabling “Chip on Heat Sink” applications or use very thin aluminium foil to create a flexible substrate.
The Nanoceramic layer is made up of tiny crystals of alumina – a material which, although it is a powerful electrical insulator, has a good thermal conductivity. This makes it an ideal dielectric – providing it can be applied densely and uniformly. This is the secret of Nanotherm’s patented electro-chemical oxidation (ECO) process.
This nano-crystalline structure has a grain size of 20~40nm. These grains are atomically bonded to the surface of the aluminium, and are packed very densely across the surface – forming an electrically impervious barrier. With such a fine crystal structure, the material retains aluminium’s natural flexibility – giving an ability to create flexible thermally conductive substrates on thin aluminium foils, but also high resistance to temperature cycling.
Finally, the dielectric material is fully inorganic. Unlike epoxy or polymer dielectrics, a Nanotherm dielectric can withstand high temperatures – it is unlikely that the ceramic will fail below the aluminium backplate’s melting point!
|Composition:||Nano-crystalline aluminium oxide (alumina, Al2O3)|
|Crystalline grain size:||20-40nm|
|Thermal conductivity:||6-7.2 W/mK|
Rth = 0.02 °C.cm2/W
|Layer thickness:||3-30 µm|
|Temperature resistance:||> 500 °C (limited by melting point of aluminium)|