RESUMO
Flexible and stretchable thin-film transistors (TFTs) are crucial in skin-like electronics for wearable and implantable applications. Such electronics are usually constrained in performance owing to a lack of high-mobility and stretchable semiconducting channels. Tellurium, a rising semiconductor with superior charge carrier mobilities, has been limited by its intrinsic brittleness and anisotropy. Here, we achieve highly oriented arrays of tellurium nanowires (TeNWs) on various substrates with wafer-scale scalability by a facile lock-and-shear strategy. Such an assembly approach mimics the alignment process of the trailing tentacles of a swimming jellyfish. We further apply these TeNW arrays in high-mobility TFTs and logic gates with improved flexibility and stretchability. More specifically, mobilities over 100 square centimeters per volt per second and on/off ratios of ~104 are achieved in TeNW-TFTs. The TeNW-TFTs on polyethylene terephthalate can sustain an omnidirectional bending strain of 1.3% for more than 1000 cycles. Furthermore, TeNW-TFTs on an elastomeric substrate can withstand a unidirectional strain of 40% with no performance degradation.
RESUMO
On-skin electronics require minimal thicknesses and decent transparency for conformal contact, imperceptible wearing, and visual aesthetics. It is challenging to search for advanced ultrathin dielectrics capable of supporting the active components while maintaining bending softness, easy handling, and wafer-scale processability. Here, self-delaminated aramid nanodielectrics (ANDs) are demonstrated, enabling any skin-like electronics easily exfoliated from the processing substrates after complicated nanofabrication. In addition, ANDs are mechanically strong, chemically and thermally stable, transparent and breathable, therefore are ideal substrates for soft electronics. As demonstrated, compliant epidermal electrodes comprising silver nanowires and ANDs can successfully record high-quality electromyogram signals with low motion artifacts and satisfying sweat and water resistance. Furthermore, ANDs can serve as both substrates and dielectrics in single-walled carbon nanotube field-effect transistors (FETs) with a merely 160-nm thickness, which can be operated within 4 V with on/off ratios of 1.4 ± 0.5 × 105 , mobilities of 39.9 ± 2.2 cm2 V-1 s-1 , and negligible hysteresis. The ultraconformal FETs can function properly when wrapped around human hair without any degradation in performance.
RESUMO
Stretchable interconnects with miniature widths are vital for the high-density integration of deformable electronic components on a single substrate for targeted data logic or storage functions. However, it is still challenging to attain high-resolution patternability of stretchable conductors with robust circuit fabrication capability. Here, we report a self-assembled silver nanofilm firmly interlocked by an elastomeric nanodielectric that can be photolithographically patterned into microscale features while preserving high stretchability and conductivity. Both silver and dielectric nanofilms are fabricated by layer-by-layer assembly, ensuring wafer-scale uniformity and meticulous control of thicknesses. Without any thermal annealing, the as-fabricated nanofilms from silver nanoparticles (AgNPs) exhibit conductivity of 1.54 × 106 S m-1 and stretchability of â¼200%, which is due to the impeded crack propagation by the underlying PU nanodielectrics. Furthermore, it is revealed that AgNP microstrips defined by photolithography show higher stretchability when their widths are downscaled to 100 µm owing to confined cracks. However, further scaling restricts the stretchability, following the early development of cracks cutting across the strip. In addition, the resistance change of these silver interconnects can be decreased using serpentine architectures. As a demonstration, these self-assembled interconnects are used as stretchable circuit boards to power LEDs.
