Ageing and vapor chopping effect on the properties of MgO thin films

• Air exposure ageing effect on the basic properties of MgO thin film is studied.
• Vapor chopping technique is used to modify the properties of MgO thin films.
• Ageing inhibits due to thin film’s quality improvement by vapor chopping.
• Vapor chopped films show better device performance than non-chopped thin films.

Nanoscale magnesium oxide thin films have been prepared on glass substrates by thermal oxidation (in air) of vacuum evaporated magnesium films. The ageing (air exposure) effect for 1, 10, 20 and 30 days on the various properties of MgO thin films was studied. The ageing effect on the optoelectronic devices i.e. optical waveguide and plasma display panel’s performance was examined by measuring their optical transmission loss and secondary electron emission yield, respectively. Vapor chopping technique was employed for thin film quality improvement followed by ageing inhibition. The firing voltage for fresh vapor chopped (VC) MgO thin films was in 125–150 V range, which shifted to 140–178 V after 30 days, whereas in the non-chopped (NC) films it increased up to 165–210 V from 140–160 V. After 30 days ageing, NC thin film surface morphology changed from polished to dull due to wrapped moisture like layer, whereas VC thin film morphology was unpretentious. The XPS analysis also confirmed the VC MgO thin films superior sustainability against the ageing than NC films.