Melt-growth of single-crystal alloy semiconductor structures and semiconductor assemblies incorporating such structures

A single-crystal alloy semiconductor structure or method of fabricating the same comprising: forming a seed 7 containing an alloying material on a substrate 3; providing a structural form 11 of a host material on the substrate which is crystallized to form the single-crystal alloy semiconductor structure, the structural form comprising a main body 31 which extends from the seed and a plurality of elements 33 connected in spaced relation to the main body; applying heat such that the structural form has a liquid state; and cooling such that the structural form nucleates at the seed and crystallizes as a single crystal to provide an alloy semiconductor structure. In one embodiment, the plurality of elements provide reservoirs of the alloying material in liquid state, such that successive ones of the plurality of elements act to maintain, in liquid state, an available supply of the alloying material to a growth front of the single crystal in the main body of the respective structural form. In one embodiment the host material may be germanium and the alloying material may be silicon.