A surface acoustic wave device that is suitable for mass production and that has excellent operational performance at the superhigh-frequency range. Access concentrators are employed at the customer premises, remote concentrators and optional relay nodes are employed in the local loop, and transfer switches are employed in the central office. A locking frame 14 to be coupled with the upper LED lamp module 34 is formed on said base 12. 02 includes carrying out a sintering in an inert gas atmosphere with an oxygen concentration of 9 ppm to 1% and wherein a treatment at an elevated temperature in an oxidizing atmosphere after the sintering is not carried out.