The effect of rapid thermal annealing (RTA) on radio frequency (rf) sputtered amorphous silicon carbide films prepared under different hydrogen partial pressures (PH) was examined. The structural study showed that the effect of RTA on the film properties was similar to that of furnace annealing. Therefore, the mechanisms suggested for furnace annealing could equally be applied to the RTA case. The electrical results showed that the effects of RTA and furnace annealing on interface trapped charge density (Dit) for the unhydrogenated films can be explained satisfactorily using the conclusions obtained from the structural study. For the hydrogenated films, the influence of annealing on Dit warrants further investigation.

The electrical results of rf sputtered hydrogenated amorphous silicon carbide (a-Si1−xCx:H) films prepared under different sputtering conditions are presented. It was found that hopping and Poole–Frenkel effects are the conduction mechanisms for low and high applied fields, respectively. From the capacitance versus voltage measurements, the fixed charge density (Qf) and the interface trapped charge density (Dit) were found to be in the range of 5.5–6.81×1010 cm−2 and 5–13×1011 eV−1 cm−2, respectively. Dit decreases with either an increase in the total sputtering pressure, the partial hydrogen pressure, or the substrate temperature, but increases with an increase in the rf sputtering power. The decrease in Dit was found to be closely related to the increase in the number of silicon–hydrogen bonds.

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Temporal information is an important characteristic of event. It can be used in information retrieval process to organize the returned result. In Chinese, the presentations of time expression are very complex, which make it difficult to both accurately recognize a time expression and precisely connecting it with a given event in a web page that contains multiple events. To address these problems, this paper presents an innovative event time extraction model. Rather than just rely on local context within a web page or a text, this model applies global context provided by all the web pages that had been automatically judged as related with a given event. Our experiment results based on the evaluation criterions show the feasibility of the provided model.