Growth and Characterization of Silicon Carbide Thin Films Using a Nontraditional Hollow Cathode Sputtering Technique

Silicon carbide (SiC) is considered a suitable candidate for high-power, high-frequency devices due to its wide bandgap, high breakdown field, and high electron mobility. It also has the unique ability to synthesize graphene on its surface by subliming Si during an annealing stage. The deposition of SiC is most often carried out using chemical vapor deposition (CVD) techniques, but little research has been explored with respect to the sputtering of SiC. Investigations of the thin film depositions of SiC from pulse sputtering a hollow cathode SiC target are presented. Although there are many different polytypes of SiC, techniques are discussed that were used to identify the film polytype on both 4H-SiC substrates and Si substrates. Results are presented about the ability to incorporate Ge into the growing SiC films for the purpose of creating a possible heterojunction device with pure SiC. Efforts to synthesize graphene on these films are introduced and reasons for the inability to create it are discussed. Analysis mainly includes crystallographic and morphological studies about the deposited films and their quality using x-ray diffraction (XRD), reflection high energy electron diffraction (RHEED), transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), Auger electron spectroscopy (AES) and Raman spectroscopy. Optical and electrical properties are also discussed via ellipsometric modeling and resistivity measurements. The general interpretation of these analytical experiments indicates that the films are not single crystal. However, the majority of the films, which proved to be the 3C-SiC polytype, were grown in a highly ordered and highly textured manner on both (111) and (110) Si substrates.

Ellipsometric Study of Single-Crystal γ-Inse From 1.5 To 9.2 Ev

We report the component E ┴ c of the pseudodielectric-function tensor <ε(E)> = <ε1(E)> + i< ε2(E)> of γ-phase single-crystal InSe, obtained from 1.5 to 9.2 eV by vacuum-ultraviolet spectroscopic ellipsometry with the sample at room temperature. Overlayer artifacts were reduced as far as possible by measuring fresh surfaces prepared by cleavage. Accurate critical-point energies of observed structures were obtained by a combined method of spectral analysis.

“PROVINCIALISM, PICKING SIDES AND BIAS: EFFECTS OF GEOGRAPHY ON MEDIA COVERAGE OF CRYSTAL BRIDGES MUSEUM OF AMERICAN ART, 2005-10.”

The development of Crystal Bridges Museum of American Art in Bentonville, Arkansas, by Wal-Mart heiress Alice Walton has prompted diverse coverage from print and online media. This investigation looked at trends in news stories and commentary from 2005-10 to show how the location of a medium affected coverage. Through the author’s own observations and interviews with journalists and other interested parties, several trends emerged. Media outlets outside Arkansas portrayed the museum as trying to plunder the cultural heritage of local communities and relied partly on the museum’s association with Wal-Mart and stereotypes of Arkansas to frame coverage. Arkansas media, faced with limited cooperation from the museum’s public relations apparatus, typically played a cheerleader role, at times overemphasizing the importance of the collection in the art world and showcasing few critical voices in stories about acquisitions and other areas of the museum’s development.