Low temperature (150 °C) deposition of doped and undoped polycrystalline Si (poly-Si) as well as SiN X films on polyethylene terephthalate (PET) films has been achieved with practical deposition rates by using pulsed-plasma CVD under near-atmospheric pressure. The precursor is SiH 4 diluted in H 2 for poly-Si while N 2 has been additionally used for SiN x . No inert gases such as He was used. A short-pulse based power system has been employed to maintain a stable discharge in the near-atmospheric pressures. With this technique, deposition of poly-Si thin film with virtually no incubation layer is possible, which in the case of P-doped poly-Si shows a Hall mobility (μ H ) of 1.5 cm 2 /V·s.