Chemical vapor deposition grows thin layers of solid material from hot gas — and in this experiment, the exact temperature determines whether anything forms at all. A gallium bead sits inside an aluminum tube furnace alongside a silicon wafer coated with a nickel nitrate catalyst. The tube is sealed, pumped to vacuum, and filled with argon gas. Then the furnace ramps up at 17 degrees Celsius per minute and holds at the target temperature for twenty minutes. When you examine the wafer under an electron microscope, gallium oxide nanowires appear only above 920 degrees Celsius — revealing how temperature controls whether the hot gas produces a solid coating.