METHOD FOR TESTING AND EVALUATING METAL FATIGUE ACCELERATION

摘要

PURPOSE:To detect the occurrence of a defect for before a wire breaks down and to make it possible to shorten the time of evaluation by detecting the gradual decrease in electric resistance of a specimen. CONSTITUTION:A specimen 10, a DC source 11 and a voltage amplifier 12 are provided in an electromagnetically shielded box so as not to receive the effect of external noises. A resistor 14 (resistance value R) is connected to the sample (resistance value r) in series so as to remove the fluctuation in current value due to the minute fluctuation of the sample. The output of the amplifier 12 is inputted into a power spectrum analyzer 15. The power spectrum intensity with respect to the number of vibrations is measured in order to analyze the fluctuation in voltage corresponding to the degree of fatigue of the sample. In general, wire breakdown defects of metal wirings and the like are caused by the occurrence and the growth of void cores due to the diffusion and concentration of lattice defects. The formation of the void core appears as the gradual decrease in resistance. Therefore, when the fluctuation in electric resistance is checked and the gradual decrease in resistance fluctuation is detected, the formation of the void core can be detected.