Solution-Based Fabrication of Polycrystalline Si Thin-Film Transistors from Recycled Polysilanes

Currently, research has been focusing on printing and laser crystallization of cyclosilanes, bringing to life polycrystalline silicon (poly-Si) thin-film transistors (TFTs) with outstanding properties. However, the synthesis of these Si-based inks is generally complex and expensive. Here, we prove that a polysilane ink, obtained as a byproduct of silicon gases and derivatives, can be used successfully for the synthesis of poly-Si by laser annealing, at room temperature, and for n- and p-channel TFTs. The devices, fabricated according to CMOS compatible processes at 350 °C, showed field effect mobilities up to 8 and 2 cm²/(V s) for n- and p-type TFTs, respectively. The presented method combines a low-cost coating technique with the usage of recycled material, opening a route to a convenient and sustainable production of large-area, flexible, and even disposable/single-use electronics.