Highly conductive and flexible fiber for textile electronics obtained by extremely low-temperature atomic layer deposition of Pt

Thermal atomic layer deposition (ALD) of metal has generally been achieved at high temperatures of around 300 degrees C or at relatively low temperatures with highly reactive counter reactants, including plasma radicals and O-3, which can induce severe damage to substrates. Here, the growth of metallic Pt layers by ALD at a low temperature of 80 degrees C is achieved by using [(1,2,5,6-eta)-1,5-hexadiene]-dimethyl-platinum(II) (HDMP) and O-2 as the Pt precursor and counter reactant, respectively. ALD results in the successful growth of continuous Pt layers at the low temperature without any reactive reactants owing to the low activation energy of the HDMP precursor for surface reactions. Because of the high reactivity of the precursor, the growth of a pure Pt layer is achieved on various thermally weak substrates, leading to the fabrication of high-performance conductive cotton fibers by ALD. A capacitive-type textile pressure sensor is successfully demonstrated by stacking elastomeric rubber-coated conductive cotton fibers perpendicularly and integrating them onto a fabric with a 7 x 8 array configuration to identify the features of the applied pressure, which can be effectively utilized as a new platform for future wearable and textile electronics.