The nondestructive thermoacoustic method of determination of the air-tightness of metal packagings of transistors

Abstract

The paper presents a new, nondestructive method of determination of the air-tightness of metal packagings of transistors. This method is based on the thermoacoustic approach with a microphone detection. Thermoacoustic approach means that the sound is generated by the periodical temperature of the element caused by the periodical electric power dissipation in it. In the paper both the experimental thermoacoustic frequency characteristics as also the theoretical approach applied for numerical interpretations of experimental data are presented and discussed.