Polyethylene terephthalate(PET)films are treated by argon plasma in the chambers of RF-PECVD system.In situ optical emission spectroscopy(OES)measurements are used to study the influence of different treatment parameters(discharge power,pressure)on the intensity of glow discharge.The measurement results of transmittance spectra,AFM,SEM show that the surface morphology of PET films and the properties of PET/ITO films are both improved.Finally,single junction a-Si:H solar cells with p-i-n superstrate type on ...