PURPOSE: To form thin films having a uniform thickness on respective wafers by uniformalizing the amts. of the gases released from gaseous raw material introducing pipes provided in the axial direction of a reaction tube at respective parts in a reaction tube at the time of simultaneously forming the thin films on the plural wafers with the plasma CVD device.
CONSTITUTION: The plural susceptors mounted with the wafers 1 are disposed in the reaction tube 4 of the plasma CVD device. The reaction tube 4 is internally evacuated to a reduced pressure and is heated by a heater 6. Gaseous TEOS as a reactive gas A and gaseous O2 as a gaseous raw material B are introduced from respective supply pipes 5a, 5b into the reaction tube 4 when the prescribed temp. is attained. A high-frequency electric power is simultaneously made from a power source 3 to generate a glow discharge, by which the gases A, B are activated and are brought into reaction. The SiO2 films which are reaction products are thus formed on the wafers 1. The diametrs of many release holes 9a, 9b provided in the gas introducing pipes 5a, 5b are gradually increased toward the downstream in the right direction of the reaction tube 4, by which the concns. of the gases A, B in the reaction tube 4 are uniformalized over the entire part and the SiO2 films having the uniform thickness are formed on the plural wafers 1.
OSHIBA HISASHI
TSUNEOKA MASATOSHI
FUJI PHOTO FILM CO LTD