In crystalline thin film growth of a prerequisite is substrate surfaces with stable and uniform structure and chemical composition. Various substrate treatments were used to obtain

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This study explores how project-based learning in combination with other pedagogical scaffolding approaches influences students' experiences during their transition into the university. Based on the thematic analysis of interviews with students at the end of the first semester, we show how a project-based course in electronics can create opportunities within three themes: student socialisation, curriculum integration, and peer-learning. In the light of these findings, we discuss how students build relationships with other students, as well as with faculty members and practicing engineers, and how these relationships influence their start at the university. On a more general level, this case study exemplifies how an existing electrical engineering programme can be changed by targeted interventions without the need for programme wide adjustments.

Using strain, i.e. subtle changes in lattice constant in a thin film induced by the underlying substrate, opens up intriguing new ways to control material properties. We present a study of the effects of strain on structural and ferromagnetic properties of (1 1 1)-oriented LaSrMnO epitaxial thin films grown on NdGaO, SrTiO, and DyScO substrates. (The subscript pc denotes the pseudo-cubic symmetry.) The results show that LaSrMnO assumes a monoclinic unit cell on NdGaO and DyScO and a rhombohedral unit cell on SrTiO. For LaSrMnO on NdGaO and DyScO a uniaxial magnetic anisotropy is found, while LaSrMnO on SrTiO is magnetically isotropic. The Néel model is used to explain the anisotropy of the thin films on NdGaO and SrTiO, however, for LaSrMnO on DyScO the effect of octahedral rotations needs to be included through the single ion model. Through examination of the Curie temperature of the strained films we suggest that (1 1 1)-strain has a different effect on the Jahn-Teller splitting of e and t electron levels than what is seen in (0 0 1)-oriented LaSrMnO thin films.

The magnetic anisotropy of films of La0.7Sr0.3MnO3 grown on vicinal (111)-oriented SrTiO3 substrates are investigated. For temperatures above the tetragonal -cubic structural phase transition temperature of the substrate, a step edge induced uniaxial magnetic anisotropy is found at remanence, with a thickness-driven change in easy axis direction, from perpendicular to the step edges to parallel to the step edges with increasing thickness. The anisotropy constant for the investigated (111)-oriented samples is of the same magnitude as for previously reported (001)-oriented samples. The data is discussed in the framework of in-plane rotations of the oxygen octahedra resulting in a uniaxial anisotropy. Furthermore, the magnetic anisotropy is sensitive to the structural phase transition at 105K of the substrate, and the anisotropy constant increases drastically as the temperature is lowered below 105K.