Abstract
Growth of high-quality dilute magnetic semiconductor (DMS) material is often compromised
by the low solubility of magnetic dopants, leading to formation of precipitates. Here, we explore
the feasibility of growing precipitate-free Mn-doped Ge at doping levels near the kinetic solubility
limit. Ge:Mn DMS films were grown at low temperature so as to minimize precipitate formation.
Meanwhile, epitaxial quality was maintained by employing a very low growth rate. The magnetic
properties of these lightly doped films exhibit both interesting contrasts and similarities with those
of heavily-doped DMS reported in the literature, indicating that the substitutional Mn contents are
very similar. Films grown at 95 degree C are free of intermetallic precipitates, offering useful opportunities for studying the fundamentals of carrier mediated exchange and metal insulator transitions without complications arising from precipitate formation.