Novel metal-oxides (MOx) semiconductors for thin-film transistors (TFTs) are being developed as they can offer superior electric performances over organic-based counterparts. MOx TFTs processed on foil could be exploited in smart labels as RFID and NFC tags, flexible wearable devices, interfaced with or like sensors for personalized healthcare, fulfilling the demand for device integration in daily life products. However, their current processing conditions do not enable large-area manufacturing on commonly used substrates in printed electronics, such as thermosensitive polyethylene-based foils, preventing their cost-effective diffusion in consumer and logistic products. This thesis addresses the solution processing at low temperature (<200°C), via deep-UV enhanced synthesis, of metal-oxide-based TFTs and their additive manufacturing, including ink development and printing, and TFT fabrication and characterization. First, we present bottom gated TFTs made from a novel, fully solution-processed IZO/AlOx-based stack. On silicon, we studied how thermally annealed IZO (200-450°C) interacts with high-k AlOx-based spin-coated and vacuum-deposited dielectrics by evaluating TFT performances and IZO chemical composition. The optimal material match in the sol-gel-based stack processed at 450°C resulted in superior interface and TFTs overperforming their ALD counterparts, u~26cm2/Vs, Ion/Ioff~106 versus u~4cm2/Vs, Ion/Ioff~104. Finally, fully solution-processed metal-oxide TFTs at high temperature were achieved by implementing photolithography, resulting in high-performance devices with u~68cm2/Vs and Ion/Ioff ratio>109, comparable with state-of-the-art sputtered devices. Then, we implemented a DUV-enhanced protocol for the synthesis of spin-coated IZO semiconductor and printed AlOx/YAlOx dielectric at a low temperature of 200°C. Prolonged DUV exposure (1h) and thermal annealing (3h) yielded TFTs with u as high as ~40cm2/Vs. By studying the effects of the process parameters on IZO chemical composition and TFTs characteristics, the IZO synthesis time was shortened to ~1h while maintaining excellent performances such as u~16cm2/Vs, Ion/Ioff>108, and SS<100mV/dec. Ultimately, we demonstrated a protocol as short as 10min at 200°C capable of yielding TFTs with mobility of ~3cm2/Vs, Ion/Ioff>108, and SS<100mV/dec, stable after one year without passivation. Aiming at further reducing the thermal budget, we explored an in-situ DUV excimer synthesis approach and inkjet printing of the MOx functional layers. First, DUV excimer was implemented on the AlOx/YAlOx dielectric, demonstrating at a very low processing temperature of 130°C, capacitors (MIM) exhibiting leakage currents of about 10-7A/cm at 1MV/cm. We proposed and validated a process flow to integrate these MIMs on flexible foil, resulting in operative MIMs with a printed AlOx/YAlOx dielectric on PEI foil. We developed an IZO ink and studied composition influences on printability and TFT performance when synthesized at temperatures below 200°C. The combination of DUV excimer treatment at 180°C with an optimized IZO ink formulation and printing process resulted in TFTs with u>1cm2/Vs. Finally, thermally annealed TFTs with printed MOx functional stack exhibiting u>4cm2/Vs were proven. Process tuning is still required to achieve fully printed IZO-AlOx/YAlOx TFTs on foil, but the preliminary results proved the suitability of both printing and synthesis approaches with cost-effective polymeric substrates.