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Magnesium is an essential mineral in the human body and has recently been studied as a bioabsorbable material for use
in cardiac stents. New areas of application can be found in bone plates, bone screws, and orthopedic implants.
Magnesium alone has a corrosion rate much too high for use in such applications and has been alloyed with various
elements to improve corrosion resistance. The use of vapor deposition to create Mg alloys for the above applications has
not been attempted although certain properties of non-equilibrium alloys, namely corrosion resistance, can be improved.
Using vapor deposition the characterization of the growth of magnesium alloy thin films has been done utilizing various
alloying elements, substrate temperatures, post-deposition treatments, and substrate positions. The results point towards
a growth mode controlled by crystallization of the Mg. Mg Sculptured thin films (STFs) are used to demonstrate these
effects and potential solutions while also providing a route to control nanoscale surface morphology to enhance cell
growth, cell attachment, and absorption properties. The results of the study are presented in terms of x-ray diffraction
data, microscopy analysis of growth evolution, and corrosion testing. This magnesium alloy research utilizes a dual
source deposition method that has also provided insight about some of the growth modes of other alloy STFs.
Engineering of surface morphology using dip coatings and etching has been used in biomedical materials to enhance
certain application specific surface properties. STF technology potentially provides a path to merge the advantages of
non-equilibrium alloy formation and engineering nanoscale surface morphology.
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