Formation mechanism and ordered patterns in Cu films deposited on silicone oil surfaces

A copper (Cu) film system, deposited on silicone oil surfaces by vapor phase deposition method, has been fabricated and its formation mechanism as well as ordered patterns has been studied. The formation mechanism of the films obeys the two-stage growth model. The ordered patterns, which are composed of a large number of parallel keys with different width w but nearly uniform length L, are observed in the continuous Cu films. It is noted that, if the nominal film thickness d=120.0nm, the value of α=L/(4w) reaches its maximum at the deposition rate f=0.05nm/s. The experiment indicates that the ordered patterns mainly result from the ordered material aggregation, which depends closely on the internal stress in the nearly free sustained Cu film system.