17.3: aSi:H Thinfilm Transistors with a New Hybrid Dielectric Highly Stable under Mechanical and Electrical Stress

Abstract

AbstractA resilient, homogeneous, hybrid of silicon dioxide and silicone polymer deposited at roomtemperature replaces the conventional, brittle, silicon nitride barrier layer and gate insulator in amorphous silicon thinfilm transistorsaSi:H TFTs on flexible polyimide foil. The electron fieldeffect mobility is high at 1.6 cm2/V⋅s, and the threshold voltage shift under high gate bias is comparable to that in conventional aSi:H/SiNx TFTs fabricated at 300°C. The substhreshold slope is 290 mV/decade. The new transistors are highly flexible, as they can be bent down to 0.5 mm radius 5% strain in tension and down to 1mm radius 2.5% strain in compression. These TFTs qualify for rollout screens of handheld devices.