Abstract: Provided is a method capable of predicting the warpage caused when a silicon wafer is subjected to heat treatment taking into account the effect of oxygen and a method of producing a silicon wafer. The method includes: determining the mobile dislocation density, the stress, and the time evolution of the strain of the silicon wafer being subjected to heat treatment from the rate of change in the strain and the rate of change in the mobile dislocation density; and determining the magnitude of plastic deformation of the silicon wafer as a warpage. The mobile dislocation density Ni at the start of the heat treatment is given as: Ni=A×(?Oi×L?Lo)2.5??(1), where A and L0: constants, ?Oi: the concentration of oxygen used by oxygen precipitates in the silicon wafer at the start of the heat treatment, L: the mean size of the oxygen precipitates at the start of the heat treatment.

Abstract: Provided is a method capable of predicting the warpage caused when a silicon wafer is subjected to heat treatment taking into account the effect of oxygen and a method of producing a silicon wafer. The method includes: determining the mobile dislocation density, the stress, and the time evolution of the strain of the silicon wafer being subjected to heat treatment from the rate of change in the strain and the rate of change in the mobile dislocation density; and determining the magnitude of plastic deformation of the silicon wafer as a warpage. The mobile dislocation density Ni at the start of the heat treatment is given as: Ni=A×(?Oi×L?L0)2.5??(1), where A and L0: constants, ?Oi: the concentration of oxygen used by oxygen precipitates in the silicon wafer at the start of the heat treatment, L: the mean size of the oxygen precipitates at the start of the heat treatment.

Abstract: There is provided an effector for providing a musical tone with an effect such as a delay, a reverberation, a chorus and the like. The effector is capable of providing a feeling of listening such that the direct tone and the effect tone unites with each other, and in addition providing a feeling of expanse effective in a sound field. An effect tone signal is divided into a low register component and a high register component. The low register component is mixed with a musical tone signal (direct tone) entered through an input terminal and then outputted. The high register component is outputted in the form of stereophonic signal as it is.