Printing Conductive Paths for Electronic Functional Devices

Printing inorganic and organic materials has been attracting plenty of researchers and scientists as an alternative to the conventional photolithography and electroless deposition methods due to the complications, time-consuming, size restrictions and high costs that these methods usually experience. Soft lithographic techniques and inkjet printing technology have offered simpler, lower costs and faster alternatives. One of the main objectives of this study is the contribution to these alternatives by utilising a cost-effective, simple and easy-to-use stamp printing machine in the deposition of metal patterns from poly(dimethylsiloxane) (PDMS) stamps onto treated glass substrates. Two drop-on-demand inkjet printers; one is a commercial desktop piezoelectric printer and a second thermal PEL printing and coating platform, were utilised to inkjet print functional materials. The cheap piezoelectric one used to deposit silver nanoparticles and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) inks. By utilising this technology, innovative flexible information storage devices, electronic memory cells, were inkjet printed. All the components (silver electrodes and PEDOT:PSS active layer) of these memory devices were fully deposited by this simple desktop inkjet printer on a flexible substrate (ceramic coated PEL paper) at room temperature. The thermal printing machine, on the other hand, was employed to print graphene oxide on the PEL paper. These techniques also provide hope to develop environmentally friendly processes of fabrication used in the electronics and semiconductor industry and minimise the wastage of materials and power.