A method for manufacturing a silicon wafer is characterized by performing one or both of grinding and polishing to a thin discoid silicon wafer to give bowl-shaped warpage that is concave at a central part to a wafer surface. The composition comprises a binder in which is dispersed a conductive pigment and a source of silicon. A determination may be made with regard to the presence of a noise component in at least one of the microphone signals based on the cross correlation coefficients, the first autocorrelation coefficients, and the second autocorrelation coefficients. The stabilizer includes a pinned ferromagnetic layer adjacent to the free layer, and an antiferromagnetic layer positioned thereon. The proxy function provides the media recommendations to the first peer device. This signal loops back and is received by the input terminal.