TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Process: The process further comprises at least one crucible, in which at least one of gallium metal and an alkali metal is placed in the one zone; at least one crucible provided in the basket structure; a frame, where the frame configured for transporting the basket structure, a baffle, and a seed rack into the autoclave before commencing crystal growth and configured for transporting the basket structure, the baffle, and the grown crystals out of the autoclave at the conclusion of a crystal growth run; and incorporating a getter material and/or structure within a vicinity of either or both the one zone or/and the other zone. Preferred Components: The basket structure comprises one or more support structures made of one or more materials of copper, copper-based alloy, gold, gold-based alloy, silver, silver-based alloy, palladium, platinum, iridium, ruthenium, rhodium, osmium, titanium, vanadium, chromium, iron, iron-based alloy, nickel, nickel based alloy, zirconium, niobium, molybdenum, tantalum, tungsten, rhenium, silica and/or alumina. The crucible comprises at least one of molybdenum, tantalum, niobium, iridium, platinum, palladium, gold, silver, tungsten, alumina, magnesia, calcia, zirconia, yttria, aluminum nitride and gallium nitride. The autoclave has an inner diameter of greater than 50 (preferably greater than 200) mm. The gallium-containing feedstock comprises at least one dopant at a concentration of 1016-1021 cm-3. The dopant comprises at least one of silicon, oxygen, magnesium, zinc, iron, nickel, cobalt and manganese. The gallium-containing feedstock comprises gallium nitride with a particle size distribution of 0.020-5 inches. The getter comprises at least one of an alkaline earth metal, scandium, titanium, vanadium, chromium, yttrium, zirconium, niobium, hafnium, tantalum, tungsten, a rare earth metal, and their nitrides, amides, imides, amido-imides and halides.    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The basket structure comprises at least one of wire mesh or wire cloth, foil, or plate comprising many through-holes or openings, where the through-holes or openings have a diameter of 0.005-0.5 inch. The autoclave apparatus is configured to process one or more portions of the gallium-containing feedstock in the supercritical fluid to provide a supercritical solution comprising at least gallium containing species at a first temperature. The autoclave apparatus is configured to flow one or more portions of the supercritical solution containing the gallium containing species from the one zone through a portion of the basket into the other zone and configured to grow crystalline gallium-containing nitride material from the supercritical solution on the seed at a second temperature, the second temperature being characterized to cause the gallium containing species to form the crystalline gallium containing nitride material on the seed. EXAMPLE - None given.