Patent ID: 8578777
Filing Date: 2013-11-12
Classification: H01L

Abstract:
1. A quantitative evaluation method comprising steps of: oscillating, in a state in which an external magnetic field is applied to a silicon wafer while keeping the silicon wafer at a constant temperature, an ultrasonic wave pulse and receiving a measurement wave pulse obtained after the ultrasonic wave pulse is propagated through the silicon wafer for detecting a phase difference between the ultrasonic wave pulse and the measurement wave pulse; and calculating an elastic constant from the phase difference, wherein the external magnetic field is changed in a constant temperature state to measure an amount of the elastic constant changed corresponding to a change in the external magnetic field for evaluating a concentration of atomic vacancies in the silicon wafer, based on a relationship wherein C(T,H) is an elastic constant, N is a concentration of atomic vacancies, C 0 T is a background, g is a coupling constant of a quadrupole distortion interaction, g′ is a coupling constant of an interaction between quadrupoles, T is a temperature, H is an external magnetic field, kB is a Boltzmann constant, E(H) is energy level in a quantum state, and O(H) is a quadrupole in a quantum state.