Hydrazine vapor-based rapid and low temperature post-processing for inkjet printed conductive copper patterns

We present a useful and effective conversion process for inkjet-printed conductive copper features on common polymer substrates. The process is based on causing burst nucleation from an as-printed copper complex ion pattern by an exposure to hydrazine vapor. This hydrazine based treatment at 150 °C for 1 min leads to copper patterns with a well-sintered microstructure and resistivity of 15.18 μΩ cm. This new approach could be an alternative to a conventional hydrogen gas treatment and is suitable for organometallic or metal complex based inks as well as most commercial plastic and paper substrates for flexible and disposable electronics.