Abstract: The present invention relates to a high frequency surface acoustic wave device, which may be manufactured by the same manufacturing equipment, and with the same material, as those required for manufacturing a low frequency surface acoustic wave device. The disclosed high frequency surface acoustic wave device comprises: a piezoelectric substrate; a high acoustic velocity layer formed on the surface of the piezoelectric substrate whose acoustic velocity of the surface acoustic wave is larger than 5000 m/sec; an input transducing part; and an output transducing part; wherein the input transducing part and the output transducing part are formed in pair on or below the surface of the high acoustic velocity layer. Besides, the high acoustic velocity layer is preferably made of aluminum oxide, and formed on the surface of the piezoelectric substrate by an electron-beam evaporation process. The thickness thereof is preferably between 2 ?m and 20 ?m.

Abstract: A method of fabricating a poly silicon layer comprising the following steps is provided. First, a substrate is provided and an amorphous silicon layer is formed on the substrate. A patterned metal layer is formed on the amorphous silicon layer. Next, a pulsed rapid thermal annealing process is performed to form a metal silicide between the patterned metal layer and the amorphous silicon layer, wherein the patterned metal layer and the amorphous silicon layer are adopted for conducting thermal energy to the amorphous silicon layer such that the amorphous silicon layer is converted into a polysilicon layer. Finally, the patterned metal layer is removed. A polysilicon layer formed according to the above-mentioned fabrication method is also provided. The grains of the poly silicon layer are spherical in shape.

Abstract: A method of fabricating a poly silicon layer comprising the following steps is provided. First, a substrate is provided and an amorphous silicon layer is formed on the substrate. A patterned metal layer is formed on the amorphous silicon layer. Next, a pulsed rapid thermal annealing process is performed to form a metal silicide between the patterned metal layer and the amorphous silicon layer, wherein the patterned metal layer and the amorphous silicon layer are adopted for conducting thermal energy to the amorphous silicon layer such that the amorphous silicon layer is converted into a polysilicon layer. Finally, the patterned metal layer is removed. Accordingly, the above processes may prevent the poly silicon layer from metal contamination.

Abstract: A method of fabricating a poly silicon layer comprising the following steps is provided. First, a substrate is provided and an amorphous silicon layer is formed on the substrate. A patterned metal layer is formed on the amorphous silicon layer. Next, a pulsed rapid thermal annealing process is performed to form a metal silicide between the patterned metal layer and the amorphous silicon layer, wherein the patterned metal layer and the amorphous silicon layer are adopted for conducting thermal energy to the amorphous silicon layer such that the amorphous silicon layer is converted into a polysilicon layer. Finally, the patterned metal layer is removed. Accordingly, the above processes may prevent the poly silicon layer from metal contamination.