Influence of the deposition of PECVD hydrogenated silicon nitride on the transparency of indium tin oxide underlayer

The effect of the deposition of PECVD hydrogenated silicon nitride (SiNx:H) on indium tin oxide underlayer has been investigated. PECVD SiNx:H films were deposited with various film thickness, substrate temperature, gas flow rate, pressure, and RF power. Two kinds of ITO films prepared either ex-situ or in-situ thermal annealing methods are examined by PECVD SiNx:H deposition. Experimental results have shown that the formation of whitened ITO is related to redundant reactive species from SiH4 and H-2 during the initial stage of SiNx:H deposition. NH3/SiH4 flow ratio is found to be one of the key factors to affect whitening of ITO films during SiNx:H deposition. In-situ annealed ITO films could be more chemically stable than ex-situ annealed ones since in-situ annealed ITO films have less optical degradation than ex-situ annealed ones after PECVD SiNx:H deposition.