| 摘要 |
<p>PROBLEM TO BE SOLVED: To find a defective bonding by a method in which voltage and current waveforms of an ultrasonic oscillator are sampled in real time during bonding and the data are input to be converted into digital one and the digital data are stored for each pin and the present data is compared with the average data of a plurality of the past data. SOLUTION: Voltage and current waveforms of an ultrasonic oscillator 21 are fetched and converted into digital data by A/D converters 11, 12. From the digital data, the frequencies, a phase difference between the voltage and the current waveform, and impedances are calculated by a digital signal processing means 13 and the obtained digital data is stored for each pin in a data storing means 14. The average data of a plurality of the past digital data and the present digital data calculated by the digital signal processing means 13 are compared to find a defective bonding.</p> |
