An interconnect apparatus for testing bare semiconductor dice comprises raised contact members on a semiconductive substrate. The contact members are covered with an insulation layer and a conductive cap connected by a conductive trace to a testing circuit. The trace is covered with coaxial layers of a silicon-containing insulation and a metal for shielding the trace from “crosstalk” and other interference. An apparatus for simultaneous testing of multiple dies on a wafer has thermal expansion characteristics matching those of the semiconductor die or wafer and provides clean signals.