Gas-phase formation of self-assembled monolayers on MgO for protection against hydration.

The gas-phase adsorption of octyltrichlorosilane onto MgO produces self-assembled monolayers that can provide protection against hydration of the underlying MgO surfaces. MgO thin film has attracted attention for application as a protecting layer of alternating current plasma display panel. On exposure to air, the clean MgO surface interacts with water and quickly hydrates to Mg(OH)2, which reduces the secondary electron emission yield. The gas-phase deposition of octyltrichlorosilane on the clean MgO has produced self-assembled monolayers because of high reactivity of the MgO surface. The ultra-thin organic layer of the octylsiloxane can provide significant protection against hydration to the MgO surface, and improves secondary electron emission yield for the MgO samples. The secondary electron emission coefficient y for the monolayer-coated MgO sample is about 25% higher than that for the clean MgO after 24 hr exposing to air.