3 METHOD FOR PREPARING OF FILLING CYLINDER OF HIGHLY PURE NITROGEN TRIFLUORIDENF3 BY TREATING THE INNER SIDE OF FILLING CYLINDER AND FILLING CYLINDER PREPARED BY THE METHOD

摘要

PURPOSE: A charge container manufacturing method of high purity nitrogen trifluoride by treating the inside of the charge container early and the charge container thereby are provided to use effectively for washing of semiconductors or CVD(chemical vapor deposition) apparatus or etching without purifying additionally by keeping high purity of nitrogen trifluoride. CONSTITUTION: The surface roughness of an initial charge container is formed to be less than 1 micron by manufacturing the charge container with grinding the inner surface of the charge container. The number of particles less than 0.1 micrometer in the charge container is decreased to be less than 100/ft3 by heating and vacuum-processing the charge container ten times or more at 90-150 deg.C for three hours, and moisture is reduced to be less than 1 ppm. The charge container is made of manganese steel, carbon steel, chrome molybdenum steel and light alloy. High purity nitrogen trifluoride is stored safely by processing the inside of the charge container for cleaning the semiconductor or CVD apparatus or etching.