Sustainable and secure thin-film transistor platform with integrated optical–acoustic anticounterfeiting features for smart electronics

Thin-Film Transistors (TFTs) have evolved from display backplanes to printed, transparent, and conformal forms, paving the way for next-generation wearable, smart, and secure electronics. TFT-based anticounterfeiting architectures promise significant impact on secure electronics, offering scalable, flexible, and cost-effective protection against product forgery. In the present study, graphene oxide (GO) prepared by the modified Hummers method was reduced using ascorbic acid. Further, a NiO/rGO composite was synthesized via microwave irradiation, and its structure was confirmed by XRD, FTIR, XPS, FESEM and EDS. Commercial phosphor JUP-AS110 was mixed with NiO/rGO composite to formulate a functional screen printable ink. TFT with a staggered bottom-gate architecture was subsequently fabricated by integrating DC magnetron sputtered TiO 2 gate dielectric, screen-printed NiO/rGO active layer, and thermally evaporated Al source/drain electrodes. The TFT exhibited an n-channel behavior with a high on/off current ratio of 1.95 × 10 6 , a field-effect mobility of 0.16 cm 2 /V·s, and a subthreshold swing of 1.6 V/decade, highlighting the potential of the device for low-voltage, high-performance electronic applications. Moreover, the TFT combined built-in security features, exhibiting blue emission at 475 nm along with an audible beep using an IR taggant reader in response to near-infrared emission under 980 nm laser excitation, confirming its promise as a multifunctional smart, sustainable and secure platform for advanced anticounterfeiting applications.