Orientation control of vacuum deposited epitaxial metal films by applying external stress

Abstract

The orientation of vacuum deposited, epitaxial metal films was controlled, by applying external stress, on copper gold ordered alloy, and on gold manganese ordered alloy.Ordered tetragonal or quasi-tetragonal epitaxial films such as CuAuI and gold manganese α″ have the mixed orientation of the shorter axis normal and parallel to the film plane,in the usual deposition in vacuum, i.e., (i)when the copper was deposited immediately after the gold was deposited, on cleaved surface of rock salt and homogenized, as is shown in Fig.la., or (ii)when it is formed by flash method (the two constituent atoms are deposited simultaneously), as shown in Fig.2a. This is very troublesome for the analysis or interpretation of the ordered structure of alloys. The author controlled the orientation so that the shorter axis is overall normal to the film plane in both CuAuI and gold manganese α″ by the following way. An epitaxial gold film held at room temperature for one night was rapidly heated to 350°C (at the rate of 15°C per minute), then copper or manganese was deposited onto it at that temperature, and homogenized