Will inorganic materials eclipse organics in printed electronics?
A new report from Reportlinker.com, " Inorganic and Composite Printed Electronics 2012-2022," says that there is increasing work on printed inorganics as organisations struggle to improve the performance of organics. To achieve better conductance and cost, for the best printed batteries, for quantum dot devices and for transistor semiconductors with ten times the mobility, Reportlinker.com says to look to the new inorganics. The emerging world of new nanoparticle metal and alloy inks are miles superior in cost and also in terms of conductivity and stability. These include flexible zinc oxide based transistor semiconductors which operate at as much as at ten times the frequency of organic materials. They also offer excellent stability and life, along with many other inorganic materials. The report considers inorganic printed and thin film electronics for displays, lighting, semiconductors, sensors, conductors, photovoltaics, batteries and memory and coverage is global. Emphasis is placed on technology basics, commercialisation and the key market players. The publication also looks at device fabrication and integration. IDTechEx forecasts a market of $45 billion for printed electronics by 2022 and that market is expected to be split evenly between organic and inorganic materials. The rapidly increasing opportunities for inorganic and composite chemicals is now in new printed electronics, given that so much of the limelight is on organics. Inorganics encompass various metals, metal oxides as transparent conductors (such as fluorine tin oxide or indium tin oxide, extensively used in displays and photovoltaic technologies) or transistor materials as well as nano-silicon or copper and silver inks, whether in particle or flake form. Then there are inorganic quantum dots, carbon structures such as graphene, nanotubes and the various buckyballs among other novel devices. However, there is much more, from light emitting materials to battery elements and the amazing new meta-materials that render things invisible and lead to previously impossible forms of electronics. Over the next ten years, improvements in inorganic conductors such as the use of nanotechnology and the lack of improvement of the very poorly conductive and expensive organic alternatives means that inorganics will be preferred for most conductors whether for electrodes, antennas, touch buttons, interconnects or for other purposes. In contrast, organic substrates for flexible electronics such as low cost polyester film and paper will be preferred in most cases because they are light weight, low cost and have a wide range of mechanical flexibility. The use of inorganic substrates such as glass represents a fall-back particularly required where there is failure to reduce processing temperatures. Here stainless steel foil printed reel to reel is an improvement, where possible. In order to meet the widening variety of needs for printed and potentially printed electronics, not least in flexible, low cost form, a rapidly increasing number of elements are being brought to bear. Oxides, amorphous mixtures and alloys are particularly in evidence. Even the so-called "organic devices" such as OLEDs can employ materials such as boron, aluminium, and titanium oxide and nitrides as barrier layers against water and oxygen. They also use aluminium, copper, silver, indium tin oxide as conductors, calcium or magnesium cathodes and CoFe nanodots as well as iridium and europium in light emitting layers. The report covers a number of different technologies which include non-silicon inorganic options such as CIGS, CdTe, CdSe, GaAs, GaAs-germanium, InGaP and InGaAs as well as other alternatives such as nanorods and carbon nanotubes.