Patent ID: 8197600
Filing Date: 2012-06-12
Classification: C23C

Abstract:
1. A vaporizer for generating a process gas from a liquid material, the vaporizer comprising: a container defining a process space of the vaporizer; an injector having a spray port configured to spray the liquid material in an atomized state downward in the container; a heat-exchange lower block having an internal space and disposed below the spray port inside the container such that a run-up space for the atomized liquid material is defined between the spray port and the heat-exchange lower block, and an annular space continuous to the run-up space is defined between an inner surface of the container and the heat-exchange lower block, the heat-exchange lower block being a column having a circular or polygonal shape in cross section and configured to guide the atomized liquid material, which is flowing downward from the injector through the run-up space, into the annular space without allowing the atomized liquid material to flow into the heat-exchange lower block; an internal heater disposed in the internal space of the heat-exchange lower block and connected to a power supply disposed outside the container, the internal heater being configured to heat the atomized liquid material flowing through the annular space to generate the process gas; a gas delivery passage connected to the container to output the process gas from the annular space; and a control section preset to stop or decrease electric power supplied from the power supply to the internal heater when supply of the liquid material from the injector is stopped, wherein the column, serving as the heat-exchange lower block, is formed of an airtight casing having a wall thickness of 1 to 10 mm and has a thermal capacity decreased by being hollow, the internal space is defined by the casing and has atmospheric pressure or a vacuum pressure, and the casing is transparent to transmit infrared rays, and wherein the internal heater includes a carbon wire formed of woven bundles of carbon fibers and sealed in a ceramic envelope, the internal heater is disposed in the internal space to heat the casing from inside mainly by radiant heat, and the internal heater heats the container from inside through the transparent casing by radiant heat.