In-situ and real time scanning probe microscopy of organic ultra thin films

In recent decades, Organic Thin Film Transistors (OTFTs) have attracted lots of interest due to their low cost, large area and flexible properties which have brought them to be considered the building blocks of the future organic electronics. Experimentally, devices based on the same organic material deposited in different ways, i.e. by varying the deposition rate of the molecules, show different electrical performance. As predicted theoretically, this is due to the speed and rate by which charge carriers can be transported by hopping in organic thin films, transport that depends on the molecular arrangement of the molecules. This strongly suggests a correlation between the morphology of the organic semiconductor and the performance of the OTFT and hence motivated us to carry out an in-situ real time SPM study of organic semiconductor growth as an almost unprecedent experiment with the aim to fully describe the morphological evolution of the ultra-thin film and find the relevant morphological parameters affecting the OTFT electrical response. For the case of 6T on silicon oxide, we have shown that the growth mechanism is 2D+3D, with a roughening transition at the third layer and a rapid roughening. Relevant morphological parameters have been extracted by the AFM images. We also developed an original mathematical model to estimate theoretically and more accurately than before, the capacitance of an EFM tip in front of a metallic substrate. Finally, we obtained Ultra High Vacuum (UHV) AFM images of 6T at lying molecules layer both on silicon oxide and on top of 6T islands. Moreover, we performed ex-situ AFM imaging on a bilayer film composed of pentacene (a p-type semiconductor) and C60 (an n-type semiconductor).

Visualising In/Equalities through Contemporary Documentary Cinema. A Diffractive Reading of Feminist Practices in Spanish and Italian Non-Fiction Films

This thesis brings together feminist documentary film theory and feminist new materialism(s) to describe how feminist material-discursive practices in a sample of Spanish and Italian documentary cinema made between 2013-2018 (can) visualise gender in/equalities. The accomplished objectives have been: 1. Building a bridge between feminist documentary film theory and Karen Barad’s diffractive methodology by approaching non-fiction cinema that deals with social inequalities as a diffraction apparatus. 2. Developing a feminist toolbox for a response-able gaze by gathering different insights from feminist film theory. 3. Identifying feminist material-discursive practices in a sample of documentary films produced in Spain and Italy over the last six years (2013-2018). 4. Analysing the effects that these feminist material-discursive practices in documentary cinema have, particularly in terms of visualising gender in/equalities on both sides of the camera and on both sides of the screen. 5. Revealing patterns between the ten case studies by reading through one another (i.e. diffractively) insights raised in each one of them. In ten documentary films/case studies, I identify patterns of continuities and differences concerning feminist material-discursive practices at four levels: content, form, production and reception. In terms of contents, I detect two patterns in which feminist material-discursive practices may operate: enacting the right to appear or enacting the right to look back and/or against the grain. As for the forms, I exemplify how feminism politicises Bill Nichols’s six modes of representation. My analysis of production practices is elaborated along the filmmakers’ self-positions/situatedness, tensions/obstructions, and effects/affects/emotions regarding four key concepts: documentary cinema, equality, gender and feminism(s). And in the case of reception practices, I identify patterns of affective identification and/or intellectual reflections.