Ultralow temperature solution processed gate dielectrics using molecular structured precursors and highly energetic photochemical process

Abstract

We report a new strategy for obtaining an ultralow temperature solution derived metal-oxide dielectric such alumina, by using molecular clusters (MCs) (aluminium-oxo-hydroxy cluster, Al-13) as a precursor and local structure controllable activation process via deep-ultraviolet (DUV)-induced photochemical activation. We show that the combination of Al-13 MC precursor and the spatially controllable photochemical activation enables the formation of highly dense oxide (Al2O3) thin films at an ultralow temperature (< 60C), through an efficient integration of the dissociated skeleton of the MC precursors. Finally, to demonstrate the versatility of the ultralow-Temperature-Annealed and large area ceramic dielectrics, metal-oxide TFTs, carbon nanotube TFTs and integrated circuits were fabricated directly both on ultrathin (thickness < 3 m) polymeric and low thermal budget stretchable substrates. The metal-oxide TFTs and 7-stage ring oscillator circuits showed an average mobility of 5 cm2 V-1 s-1 with a narrow distribution of the performance and good operational stability, and oscillation frequency greater than 1 MHz with corresponding propagation delay less than 70 ns per stage, respectively.