Herein we report a prototypical electronic substrate specifically designed to serve the weakly interacting massive par-ticles (WIMPs) detectors at the China Dark Matter Experiment (CDEX). Because the bulky high-purity germanium (HPGe) detectors operate under liquid-nitrogen temperatures and ultralow radiation backgrounds, the desired electronic substrates must maintain high adhesivity across different layers in such cold environment and be free from any radioactive nuclides. To conquer these challenges, for the first time, we employed polytetrafl uoroethylene ((C2F4)n) foil as the base substrate, in conjunction with ion implantation and deposition techniques using an independently developed device at Beijing Nor-mal University for surface modification prior to electroplating. The remarkable peeling strengths of 0.88±0.06 N/mm for as-prepared sample and 0.75±0.05 N/mm for that after 2.5-days of soaking inside the liquid nitrogen were observed, while the regular standards commonly require 0.4 N/mm～0.6 N/mm for electronic substrates.