Thin-Film Electronics on a Green and Flexible Cellulose-Based Film

Flexible electronics, mostly realized on plas-tic substrates, enables various technologies to encompassa wider range of innovative applications such as wearables,implantable devices, and flexible sensors. However, thisrapidly evolving field equates to a high turnover leadingto a substantial electronic waste generation. To addressthis stark sustainability problem, research has shiftedtoward greener materials and methodologies for devicefabrication. Here, we report the realization of thin-film elec-tronics on triacetyl cellulose (TAC) film derived from astructural compound in plants called cellulose. Resistivetemperature sensors based on sputtered Cu are achieved,demonstrating a linear relationship between resistance andtemperatures up to 100 degrees C. Multilayered thin-film transis-tors (TFTs) based on InGaZnO (IGZO) are also realizedwith anON-OFFcurrent ratio approximate to 105, effective mobility of13.2 cm2<middle dot>V-1<middle dot>s-1, threshold voltage of-0.2 V, and sub-threshold swing of 161 mV<middle dot>dec-1, which are characteristicscomparable to devices fabricated on conventional plasticsubstrates. At the same time, we fabricated common-source amplifiers with a low-frequency voltage gain of4.5 dB and a cutoff frequency of 50 Hz in flat condition.These parameters minimally vary (5.6 dB and 40 Hz) whenthe circuit is mechanically deformed by bending to a radiusof 8 mm. Furthermore, the TAC film exhibits dissolvabilityin organic solvents such as acetone and acids such asacetic acid, nitric acid, and phosphoric acid. These findingsdemonstrate the potential of a cellulose-based film as analternative to plastic substrates and its merits for the real-ization of green electronics