Fabrication and Characterization of Controllable Grain Boundary Arrays in Solution Processed Small Molecule Organic Semiconductor Films

We have produced solution-processed thin films of 6,13-bis(triisopropyl-silylethynyl) pentacene with grain sizes from a few micrometers up to millimeter scale by lateral crystallization from a rectangular stylus. Grains are oriented along the crystallization direction, and the grain size transverse to the crystallization direction depends inversely on the writing speed, hence forming a regular array of oriented grain boundaries with controllable spacing. We utilize these controllable arrays to systematically study the role of large-angle grain boundaries in carrier transport and charge trapping in thin film transistors. The effective mobility scales with the grain size, leading to an estimate of the potential drop at individual large-angle grain boundaries of more than one volt. This result indicates that the structure of grain boundaries is not molecularly abrupt, which may be a general feature of solution processed small molecule organic semiconductor thin films where relatively high energy grain boundaries are typically formed. This may be due to the crystal Transient measurements after switching from positive to negative gate bias or between large and small negative gate bias reveal reversible charge trapping with time constants on the order of 10 s, and trap densities that are correlated with grain boundary density. We suggest that charge diffusion along grain boundaries and other defects is the rate determining mechanism of the reversible trapping.Comment: 12 pages, 11 figure

Transitional Experiences of Post-Secondary Students with Non-Disclosed Disabilities

The purpose of this study was to examine the transitional experiences of undergraduate students with non-disclosed disabilities and gain insight on the intentions of students choosing the route of non-disclosure in higher education. It was found that students with non-disclosed disabilities have significant challenges with managing their workloads and stress in their transition into college. Additionally, changes in support from high school to college have a significant influence on self-disclosure of disabilities. With parental guidance lacking from the participants’ support systems in post-secondary education, it was found that changes in support among the group’s transition into college may be a present factor in the participants’ decision not to disclose their disabilities. It was also found that awareness of negative stigma towards disabilities can influence disclosure and disability identity in students with invisible disabilities. For these reasons, it is important for professionals in higher education to encourage positive conversations about disability and encourage students to disclose disabilities early in their transition

Transitional Experiences of Post-Secondary Students with Non-Disclosed Disabilities

The purpose of this study was to examine the transitional experiences of undergraduate students with non-disclosed disabilities and gain insight on the intentions of students choosing the route of non-disclosure in higher education. It was found that students with non-disclosed disabilities have significant challenges with managing their workloads and stress in their transition into college. Additionally, changes in support from high school to college have a significant influence on self-disclosure of disabilities. With parental guidance lacking from the participants’ support systems in post-secondary education, it was found that changes in support among the group’s transition into college may be a present factor in the participants’ decision not to disclose their disabilities. It was also found that awareness of negative stigma towards disabilities can influence disclosure and disability identity in students with invisible disabilities. For these reasons, it is important for professionals in higher education to encourage positive conversations about disability and encourage students to disclose disabilities early in their transition