Preventing breakage of long metal signal conductors on semiconductor substrates

Abstract

An apparatus includes a volume of insulator disposed over a top surface of a semiconductor substrate, a tube of soft dielectric, and a metal conductor. The insulator has a hardness of more than approximately three gigaPascals (gPa) and the soft dielectric has a hardness of less than three gPa. The tube of soft dielectric and the metal conductor are both embedded within the volume of insulator. The tube defines a central volume and the metal conductor extends in a direction through the central volume for a distance of at least one inch. The metal conductor is encircled by the soft dielectric when the apparatus is viewed in a cross-sectional plane perpendicular to the direction. The metal conductor may include a plurality of bend portions. The metal conductor does not break when the apparatus is temperature cycled over a range from zero to eighty five degrees Celsius.