Deposition geometry and substrate motion effects on crystal texture of copper thin films.

摘要

Copper thin films were deposited with an electron beam evaporator on the amorphous SiO₂ layer of Si(100) substrates. Deposition geometry and substrate motion were utilized to investigate their effects on crystal texture. Polycrystalline films were created with thicknesses from 180nm to 1000nm, with stationary, zigzag, and helical substrate motions. Stationary films were created at 0, 40, 50, 60, 70, and 80 degrees ti zigzag and helical films were created at 60 and 80 degrees tilt. The 0 degree tilt stationary film has the expected fiber texture with a strong [111] orientation, followed by a weaker [200] orientation. Increasing the deposition tilt angle to 40 and 50 degrees, a fiber texture is still present with a strong [111] orientation and a weaker [200] orientation, but the fiber texture exhibits curvature with a preferred polar tilting perpendicular to the vapor flux direction. For deposition tilt angles >60 degrees, the texture has a transition from a fiber texture to a weak preferred orientation. The films also have [uvw] orientations other than [111] and [200] that influence the texture. The zigzag film at 60 degrees tilt had a fiber texture similar to the 50 degree tilt stationary film, while the 80 degree tilt zigzag film had a preferred orientation with [220] and [311] dominant orientations. The 60 degree tilt, helix film had a fiber texture similar to the 40 degree tilt stationary film, while the 80 degree tilt helix film had a fiber texture with a [220] and [311] orientations. Poles of the [111], [200], [311], [331], [420] orientations were superimposed on the texture plots for the 70 degree tilt stationary film and the 80 degree tilt zigzag film. The superimposed pattern closely mimicked the texture pattern of the two films. It was also found the two films had a different azimuthal rotation for certain (hkl) planes.