Plastic-compatible low resistance printable gold nanoparticle conductors for flexible electronics

Low resistance conductors are crucial for the development of ultra-low-cost electronic systems such as radio frequency identification tags. Low resistance conductors are required to enable the fabrication of high-Q inductors, capacitors, tuned circuits, and interconnects. The fabrication of these circuits by printing will enable a dramatic reduction in cost, through the elimination of lithography, vacuum processing, and the need for high-cost substrates. Solutions of organic-encapsulated gold nanoparticles many be printed and subsequently annealed to form low resistance conductor patterns. We describe a process to form the same, and discuss the optimization of the process to demonstrate plastic-compatible gold conductors for the first time. By optimizing both the size of the nanoparticle and the length of the alkanethiol encapsulant, it is possible to produce particles that anneal at low temperatures (<150°C) to form continuous gold films having low resistivity. We demonstrate the printing of these materials using an inkjet printer to demonstrate a plastic-compatible low resistance conductor technology. (C) 2003 The Electrochemical Society.