Surface and interface properties of alumina via model studies of microdesigned interfaces

Effect of Magnesium Oxide on Faceted Vicinal (0001) Surface of Aluminum Oxide

“…We observed the same surface structure also under SEM. Previously, Heffelfinger et al 15 21 also determined the equilibrium of an Al 2 O 3 cavity to consist of the same planes as those observed by Choi et al 20 but with different relative areas of the planes. In the observations of Choi et al 20 and Kitayama et al, 21 the cavities were so small that it could not be clearly determined if the corners and edges of the equilibrium polyhedra were sharp with the low-index planes meeting each other at finite angles, but the faceting of the arbitrarily selected planes indicated that the edges were indeed sharp.…”

Surface-energy-anisotropy-induced orientation effects on Rayleigh instabilities in sapphire

“…The general experimental procedures involved in developing microdesigned internal defect structures by lithographic methods have been described in several review papers [17,22] …”

“…However, it is not the variation in surface energy per se that matters, but the second derivative of the surface energy with orientation that is critical in dictating the perturbation energetics and kinetically dominant wavelengths [7]. Local [9][10][11][12], and on quantifying the effects of SEA on the morphological evolution of internal voids [9,[13][14][15][16][17][18][19][20][21][22][23][24][25] Glaeser [31] extended the analysis of Stölken and Glaeser [29] [32][33][34][35] to studies in which the equilibrium shape of both undoped and doped sapphire have been determined as a function of temperature [9-12, 22, 36].…”

Mechanisms of microstructure development at metallic-interlayer/ceramic interfaces during liquid-film-assisted bonding

“…The breakup of microlithographically processed pore channels in -24-sapphire and silicon carbide have been studied extensively. 10,[96][97][98][99][100][101][102] The effects of crystallographic orientation, surface energy anisotropy, perturbation amplitude and wavelength, impurity content, and temperature on the breakup of the pore channels were all areas of interest in the various studies. The transition from diffusion-controlled evolution kinetics to surface-attachment and nucleation-limited kinetics has proven to cause difficulties when using these studies to extract diffusivity information.…”