1. A SEMICONDUCTOR DEVICE, COMPRISING A GAS-TIGHT HOUSING, A SEMICONDUCTOR MEMBER HAVING A METALLIC ELECTRODE SURFACE MOUNTED IN SAID HOUSING, AN INTERMEDIATE CONTACT MEMBER OF METAL WHOSE THERMAL COEFFICIENT OF EXPANSION DIFFERS FROM THAT OF SAID SEMICONDUCTOR MEMBER, SAID CONTACT MEMBER HAVING A SURFACE IN FUSIONRESISTANT FACE-TO-FACE GLIDING CONTACT WITH SAID ELECTRODE SURFACE, A TERMINAL CONDUCTOR HAVING AN ELONGATED STEM AND A DISC BODY OF LARGER DIAMETER THAN SAID STEM LOCATED COAXIALLY AT ONE END OF SAID STEM ADJACENT TO SAID CONTACT MEMBER ON THE SIDE FACING AWAY FROM SAID SEMICONDUCTOR MEMBER, SAID DISC BODY AND SAID CONTACT MEMBER HAVING A RING-SHAPED ZONE OF MUTUAL CONTACT ENGAGEMENT EXTENDING ABOUT THE AXIS OF SAID STEM, THE PORTION OF SAID DISC BODY SURROUNDED BY SAID ZONE BEING FLEXIBLE IN THE DIRECTION OF SAID AXIS IN RESPONSE TO THERMAL ELONGATION