We generalise Simpson’s nonabelian Hodge correspondence to the context of projective varieties with Kawamata log terminal (klt) singularities. The proof relies on a descent theorem for numerically flat vector bundles along birational morphisms. In its simplest form, this theorem asserts that given any klt variety $X$ and any resolution of singularities, any vector bundle on the resolution that appears to come from $X$ numerically, does indeed come from  $X$ . Furthermore, and of independent interest, a new restriction theorem for semistable Higgs sheaves defined on the smooth locus of a normal, projective variety is established.

Adhesion in multi-layer thin film structures was measured using the four-point bend technique. The investigation primarily focused on layers found in the backside metalization processes of Power MOSFETs (typically in a DMOSFET or U-MOSFET structure). Variation in metal layer and substrate condition produced changes in the adhesion behavior of the systems of interest. Pt, Cu, and Ti metals were applied to Si and SiO2 surfaces with various roughnesses in order to establish the relative contributions of surface chemistry and roughness variation. G values ranging from 2 – 100 J/m2 were measured and it was found that variation in surface chemistry has a larger impact than roughness on the adhesion strength of the systems investigated. The four-point bend adhesion test was determined to be adequate for the measurement of weak to intermediate adhesion of metals on Si wafers with RMS roughness values on the order of the metal film thickness.