TECHNOLOGY FOCUS - ELECTRONICS - Preferred Components: The semiconductor has a purity of greater than 90 wt.%. The source of elemental semiconductor comprises less than or equal to 90 wt.% of the semiconductor.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The method further comprises: feeding the gaseous stream into the overhead temperature modulation zone and condensing unreacted metal halide in the overhead temperature modulation zone, returning the condensed metal halide from the overhead temperature modulation zone to the heating zone. The gaseous stream remaining after condensation in the overhead temperature modulation zone is fed to the overhead cooling zone, where at least the portion of the gaseous stream is condensed in the overhead cooling zone. In the method, a barrier in the apparatus separates the condensate in the overhead cooling zone from the overhead temperature modulation zone. The gaseous stream comprises the elemental metal, where the elemental metal is condensed in liquid or solid form in the overhead temperature modulation zone. The silicon and zinc chloride are reacted in the heating zone at a temperature of at least 910 degrees C or 756-910 degrees C at ambient pressure with zinc condensed in liquid or solid form in the overhead temperature modulation zone/in liquid form in the heating zone. In the method, unreacted zinc chloride and zinc are condensed from the gaseous stream at a temperature of 275-756 degrees C (preferably 420-756 degrees C) at ambient pressure in the overhead temperature modulation zone. The elemental metal is condensed in liquid form in the heating zone after reaction of the metal halide and elemental semiconductor. The method further comprises reacting the halide of the semiconductor and the metal from reaction of the metal halide and elemental semiconductor to form high purity elemental semiconductor at a location separate from the reaction of the elemental semiconductor and the metal halide. The step of isolating at least a portion of the gaseous stream including the halide of the semiconductor is further defined as drawing at least a portion of the gaseous stream from the apparatus. The step of isolating at least a portion of the gaseous stream including the silicon tetrachloride is further defined as drawing at least a portion of the gaseous stream from the apparatus. Preferred Components: The metal comprises zinc, copper, aluminum, magnesium, and/or sodium, the elemental semiconductor is a group IV and/or group III-V semiconductor, and the halide is based upon halogen atoms comprising chlorine, bromine, fluorine, and/or iodine. The elemental semiconductor is silicon. The metal halide is zinc chloride. The elemental metal is zinc. The halide of the semiconductor is silicon tetrachloride    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The apparatus includes a heating zone, an overhead temperature modulation zone in fluid communication with the heating zone, and an overhead cooling zone in fluid communication with the overhead temperature modulation zone, where the temperature of each zone is independently controlled. The source of the elemental semiconductor is introduced into the heating zone of the apparatus, where the metal halide and the elemental semiconductor are reacted in the heating zone of the apparatus. The metal halide is in gaseous form and the elemental semiconductor is in solid form during the reaction in the heating zone of the apparatus. The apparatus includes an overhead cooling zone in fluid communication with the overhead temperature modulation zone, where isolating step, at least a portion of the gaseous stream including the silicon tetrachloride is comprises condensing at least a portion of the gaseous stream in the overhead cooling zone.