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The bonding speed (or contact wave velocity) of silicon and fused quartz wafers has been measured as a function of temperature. The results show that the bonding process stops to operate at temperatures above 90°C and 320°C for fused quartz and bare silicon wafers, respectively. By comparing our results to infrared spectra obtained from silica gel we develop a tentative model of the bonding process. This model is based on the assumption that the initial wafer bonding process occurs via hydrogen bonds of adsorbed water. This model explains why the bonding strength increases in two distinct steps during high temperature annealing. By introducing a phenomenological time constant τ we can also account for the fact that in an intermediate temperature range the bonding strength does not depend on annealing time as it has been reported in the literature.

We investigated Se structures of different degrees of disorder ranging from a 5% up to a 95% degree of amorphization. Starting from a trigonal crystalline structure we applied different strategies to introduce disorder into the Se configurations by irradiating atoms from their crystalline equilibrium positions. According to the symmetry of the trigonal phase, we introduced three types of disorder, i.e. the first type where only atoms forming layers of complete helical chains are shifted from their original positions (the thickness of these layers is chosen to represent the chosen degree of amorphicity), the second type where only atoms in planes-of respective thicknesses-lying perpendicular to the chains are displaced and the third type where only randomly chosen atoms are shifted from their crystalline equilibrium positions. After a thermal treatment of these disordered starting configurations, we calculated structural and dynamic properties (i.e. pair-correlation function and vibrational spectrum) and compared the results to both the original crystalline data and results obtained from corresponding glass structures.

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Unbonded areas or bubbles generated at the interface of bonded silicon wafers in the temperature range of 200-800°C have been investigated. Experiments described in this paper demonstrate that the desorption of hydrocarbon contamination at the silicon wafer surfaces appears to be a necessary condition for the formation of these bubbles. SIMS data also indicate the existence of hydrocarbons at the bonding interface. It is speculated that hydrocarbon gas such as CH4 is required for bubble nucleation and that either CH4 or H2 itself or a mixture of both gases is contained in these bubbles. Finally, methods to prevent the formation of these bubbles are presented.