Diamond has many potential electronic applications, but the diamond seeding methods are generally harsh on the substrates rendering them unsuitable for integration in electronics. We report a non-abrasive, scalable and economic process of diamond film seeding using kitchen-wrap polyethylene employing hot filament chemical vapour reaction of H2S/CH4/H2 gas mixtures on Cu substrates. The fabricated diamond films were characterized with scanning electron microscopy, transmission electron microscopy and Raman spectroscopy, which confirm that the deposited film consists of a microcrystalline diamond of size in the range 0.5–1.0 µm. The synthesized diamond films exhibit a turn-on field of about 8.5 V µm−1 and long-term stability. Diamond film synthesis using polyethylene will enable the integration of diamond heat sinks into high-power and high-temperature electronic devices.