Super Flexible and High Mobility Inorganic/Organic Composite Semiconductors for Printed Electronics on Polymer Substrates

In solution-processed flexible electronics, it is challenging to obtain superior electrical and mechanical performance simultaneously. Attempts have been made to fabricate polymer doped oxide thin film transistors (TFTs), where, polymer doping frustrates the crystal structure of the parent oxide and causes amorphization. However, it also degrades the device mobility rapidly, thereby, limiting the allowable polymer content to only small values, which may not be sufficient for decisive enhancement in mechanical performance. In contrast, here an approach is proposed, where a set of water-insoluble and chemically inert polymers are chosen to form inorganic/organic composite semiconductors. Herein, these selected polymers oppose a large degree of intermixing with the parent oxide lattice at the atomic scale, promote its crystallization, and help to maintain the electrical properties of the oxide semiconductors intact, even when they're in near-equal amounts. Consequently, unaltered linear mobility of 40-45 cm(2) V-1 s(-1) can be obtained in In2O3-based inorganic/organic composite semiconductor TFTs with a near-equal weight of polymeric additives. Owing to the large polymer content, the TFTs are found to survive rigorous bending fatigue tests down to 1.5 mm bending radius without any deterioration in their electrical performance and without the formation of micro-cracks in the composite semiconductor material.