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Organic electronic devices are sensitive to water vapor and oxygen which has severely limited their widespread applications [1].For example,organic light emitting diodes(OLED)requires water vapor transmittance rate(WVTR)below 10-6gram/m2/day after encapsulation.In order to achieve long lifetime for organic electronic devices,various thin-film encapsulation technologies have been developed [2].One of the mainstream techniques is to deposit alternating inorganic and organic layers,with the inorganic layer to provide water vapor barrier and the organic layer to block pinholes and to improve flexibility.In the present work,two thin film deposition processes are reported to enable encapsulation of flexible organic electronic devices.The first process is to use dense and pinhole-free Al2O3 films(by ALD)as inorganic layers and flexible parylene C layers(by CVD)as organic layers.With the optimal thickness of 30nm Al2O3 film and 500nm parylene C,the encapsulation achieved WVTR at 10-5 g/m2/day,whereas the WVTR of pure PET without the barrier layers is 3.2 g/m2/day.The thin film encapsulated OLED exhibited a stable performance in atmosphere.The problem with the above process is that the deposition rate of ALD process is only 0.1 nm/min at 80 ℃,which is too slow to be acceptable for an industrial process.To improving deposition rate and reducing the complexity of the multilayer architectures,a new encapsulation process based on ICP-PECVD deposition of inorganic/organic alternating layers have been developed,along with an ICP-PECVD system jointly developed with Institute of Microelectronics,Chinese Academy of Sciences,for the process.The system can deposit inorganic and organic alternating layers in the same chamber and using the same precursor at low temperature(80 ℃),with HMDSO and oxygen(O2)for inorganic layer of SiOxand Ar for organic layer of SiOxCyHz,respectively.The deposition time can be reduced to 1hr 30 min with 4 dyads SiOx(50nm)/SiOxCyHz(300nm)structure,compared to more than 10hrs for ALD deposition.The as-deposited barrier film on PET substrates was measured with WVTR of 3.6× 10-5g/m2/day.The simple and high rate formation of hybrid barrier film by the low temperature ICP-PECVD process is a promising candidate for thin film encapsulation of flexible organic electronic devices.