Preferred Orientations of NiO Films Prepared by Plasma-Enhanced Metalorganic Chemical Vapor Deposition

Abstract

Thin films of nickel oxide (NiO) with NaCl-type structure were prepared on glass substrates at 400°C by plasma-enhanced metalorganic chemical vapor deposition using nickel acetylacetonate as a source material. The relationship between O2 flow rate, and preferred orientation and microstructure of the NiO films was investigated. Highly crystalline NiO film with (111) orientation was obtained at O2 flow rates as low as 3 cm3/min. As the O2 flow rate increased from 3 to 70 cm3/min, the orientation of NiO films changed from (111) to (100) and deposition rate decreased from 17 to 11 nm/min. Films with both (111) and (100) orientation had columnar structure. The origin of the preferred orientation of the NiO films was discussed.