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

A semiconductor pre-form from which at least one single-crystal semiconductor structure is fabricated, the semiconductor pre-form comprising:

• a substrate;
• at least one seed on the substrate for growth of at least one single-crystal alloy semiconductor structure, the at least one seed containing an alloying material;
• at least one structural form on the substrate which, when crystallized, forms the at least one single-crystal alloy semiconductor structure, the at least one structural form being formed of a host material and comprising a main body which comprises an elongate element which extends from the at least one seed and a plurality of branch or radiating elements which extend outwardly from the main body and are connected in spaced relation to the main body;
• wherein the plurality of elements of the at least one structural form provide reservoirs of the alloying material in liquid state when heated to a temperature above the melting point of the material of the at least one structural form, such that successive ones of the plurality of elements as spaced along the main body act to maintain during fabrication, in liquid state, an available supply of the alloying material to a growth front of a single crystal in the main body of the respective at least one structural form;
• and
• wherein when the at least one structural form is cooled such that the host material of the at least one structural form nucleates at the at least one seed and crystallizes as the single crystal to provide at least one single-crystal alloy semiconductor structure, the growth front propagates in a direction along a length of the elongate element of the main body of the respective at least one structural form away from the respective at least one seed.

A semiconductor assembly, comprising:

• a substrate;
• and
• at least one single-crystal semiconductor structure on the substrate, the at least one semiconductor structure being formed of an alloy of a host material and an alloying material and comprising a main body which comprises an elongate element which extends from at least one seed on the substrate and extends from and a plurality of branch or radiating elements which extend outwardly from the main body and are connected in spaced relation to and along the main body;
• wherein the at least one single-crystal semiconductor structure is fabricated by cooling at least one structural form such that the host material nucleates at the at least one seed and crystallizes as a single crystal to provide the at least one single-crystal alloy semiconductor structure, and wherein when the at least one structural form is cooled a growth front propagates in a direction along a length of the elongate element of the respective main body away from the respective at least one seed.