| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress loading effects in the vicinity of a furnace bottom when a nitride film is formed by a plasma assist ALD process using a batch type vertical furnace. <P>SOLUTION: A plasma assist ALD process is such that, by using a batch type vertical furnace 100 which includes a boat 101 which can have wafers placed on plural stages inside a reactor vessel 102, a plasma space 105 sandwiched between RF electrodes 106 along a side face of the reactor vessel, and supply ports F1, F2 which permit gas to be supplied from the plasma space evenly to wafers on respective stages inside the reactor vessel, it repeats cycles until a prescribed film thickness is obtained, one cycle being comprised of introducing, absorbing and purging gas to be nitrided and, by introduction of plasma-excited nitriding gas, nitriding and purging the absorbed gas to be nitrided. In the plasma assist ALD process, the flow volume of carrier gas at the time of introduction of the nitriding gas is made smaller than the amount of carrier gas at the time of introduction of the gas to be nitrided. Especially, a flow ratio between NH3 as nitriding gas and N2 as carrier gas is made to be 3 or less for N2 to 50 for NH3. <P>COPYRIGHT: (C)2012,JPO&INPIT |
