Preparation and Electrical Property of Naβ/β″-Al_2O_3 Film

Lithium and magnesium co-stabilized β/β″-Al_2O_3 films were fabricated by the reaction between the spinel-α-Al_2O_3 composite substrate and the vapour of Li_2O and Na_2O. The experimentalresults show that temperature is the main factor deternining the forming rate of the β/β″-Al_2O_3phases which cannot be obtained when the reaction taking place at below 1100℃. Dispersive spinelin the substrate call improve effectively the formation of β/β″-Al_2O_3 phases even at lower temperatures. The films obtained on composite substrate exhibit favorable electrical properties whichare comparable to that of β/β″-Al_2O_3 ceramics, although a little spinel remained in the film tosome extent reduce the ionic conductivity and at the same time increase the activation energy ofthe film.