Electrical Studies on Pentacene Thin Film Transistors with Different Channel Widths

In order to conduct electrical studies on organic thin film transistors, top-contact devices are fabricated by growing polycrystalline films of freshly synthesized pentacene over Si/SiO2 substrates with two different channel widths under identical conditions. Reasonable field effect mobilities in order of 10^-2-10^-3 cm^2V^-1s^-1 are obtained in these devices. An elaborative electrical characterization of all the devices is undertaken to study the variance in output saturation current, field effect mobility, and leakage current with aging under ambient conditions. As compared to the devices with longer channel width, the devices with shorter channel width exhibit better electrical performance initially. However, the former devices sustain the moderate performance much longer than the latter ones.     

Emerging Strategies in Stimuli-Responsive Silk Architectures

The utilization of implantable devices beseeches highly invasive surgeries considering the adversaries in the insertion of large, impliable devices through the body channels, which necessitate the development of implantable devices using biocompatible shape memory polymers. Silk displays prodigious heterogeneity in its genetic structure and physical properties in accordance with the spinning and storage process, where proteins undergo folding and unfolding. The stimuli-responsive nature of silk can be explained with the help of the structural morphology and composition of the material, where the hydrogen bonds in β-sheet domains and amorphous region act as switch points and net points, respectively. This review provides a primary attempt to enswathe all the literature available to date on the stimuli-responsive nature of silk and silk-based materials as a natural and biodegradable alternative for commercially used synthetic shape memory materials taking their elastomeric nature and reduction in glass transition temperature into account. Further constitutive model using the continuum approach has been utilized to explain the anisotropic elasticity damping effect and plastic deformation based on the α-helix chains, β-sheets, and β-spiral structures. The practicability to develop biomedical devices such as patient-specific-injectable scaffolds, drug carriers, and artificial muscles has been encompassed in this article.