EFFECT OF ION-BOMBARDMENT ON THE SURFACE-MORPHOLOGY OF ZN-FILMS SPUTTERED IN AN UNBALANCED MAGNETRON

It is well known that magnetron sputtered films of low melting point T -m materials have (due to their crystallisation at low substrate tempe ratures, T < 100 degrees C) rough and diffusely reflecting surfaces, e ven when thin, for instance about 20 nm for in films. Only extremely t hin films have a smooth and specular reflecting surface. This paper re ports on the possibility of sputtering thick films of low T-m material s with a smooth, optically specular reflecting surface using an unbala nced magnetron. To demonstrate this possibility, Zn films were studied and it was shown that a surface roughness of the film can be effectiv ely controlled by ion bombardment of the film during growth. The smoot hing of the Zn film does not depend on film thickness but on ion bomba rdment of the growing film.