We investigated the bonding-related gases trapped inside the cavities of micromachined silicon test structures that had been sealed by silicon direct bonding or anodic bonding under vacuum conditions. The gas content inside the cavities was analyzed by quadruple mass spectroscopy. The magnitude of the residual gas pressure inside the cavities for different cavity layouts and for various bonding processes was monitored. In cavities bonded by low-temperature silicon direct bonding the residual gases are reaction products originating from the mating silicon surfaces during annealing.

No abstract

Using both freshly sublimed powders and evaporated thin films, the reactivity of C , , towards molecular oxygen has been demonstrated using the techniques of X-ray diffraction, X-ray absorption, photoemission and infrared spectroscopy. At ambient temperature a molecular intercalation compound is formed, characterised by oxygenrich surface and sub-surface regions. At higher temperatures oxidation to CO, is preceded by the formation of various carbon suboxide intermediates, as reported in the literature.

No abstract

No abstract