Patent ID: 8343594
Filing Date: 2013-01-01
Classification: C23C

Abstract:
1. A film formation method for forming a silicon nitride film in a film formation apparatus, the method comprising: a stage of preparing the film formation apparatus such that the apparatus includes a process container having a process field configured to accommodate a plurality of target substrates stacked at intervals, a support member configured to support the target substrates inside the process field, a heater configured to heat the target substrates inside the process field, an exhaust system configured to exhaust gas from inside the process field, a process gas supply system configured to supply process gases to the process field so as to deposit a silicon nitride film on the target substrates, wherein the process gases include a silicon source gas, a nitriding gas, and a doping gas, and a control section configured to control an operation of the apparatus including the process gas supply system, wherein the process gas supply system includes a first gas distribution nozzle and a second gas distribution nozzle extending in vertical directions inside the process container and respectively having a first group of gas spouting holes and a second group of gas spouting holes formed thereon at predetermined intervals in the vertical directions over the process field, the first and second groups of gas spouting holes being configured to spout gas in lateral directions to form gas flows parallel with the target substrates on the support member, an exciting mechanism including a plasma generation area disposed in a space communicating with the process field and between the second group of gas spouting holes of the second gas distribution nozzle and the target substrates, a gas mixture tank disposed outside the process container and configured to mix the silicon source gas and the doping gas to form a mixture gas, a mixture gas supply line configured to supply the mixture gas from the gas mixture tank to the first gas distribution nozzle, first and third gas supply lines configured to supply the silicon source gas and the doping gas from a first supply source of the silicon source gas and a third supply source of the doping gas to the gas mixture tank, respectively, a second gas supply line configured to supply the nitriding gas from a second supply source of the nitriding gas to the second gas distribution nozzle without passing through the gas mixture tank, and first and second switching valves disposed on the mixture gas supply line and the second gas supply line, respectively, the first switching valve being present outside the process container and between the gas mixture tank and the first gas distribution nozzle; and a stage of then conducting a film formation sequence to form a silicon nitride film on a plurality of product substrates under the control of the control section, the film formation sequence comprising: heating the product substrates placed on the support member within the process field in the process container; forming the mixture gas by continuously supplying the silicon source gas and the doping gas respectively from the first and third supply sources to the gas mixture tank with the silicon source gas set at a flow rate of 50 to 2,000 sccm and the doping gas set at a flow rate of 1 to 15 sccm; supplying the mixture gas pulse-wise from the gas mixture tank through the first group of gas spouting holes of the first gas distribution nozzle to the process field while performing said forming the mixture gas; and supplying the nitriding gas pulse-wise from the second supply source through the second group of gas spouting holes of the second gas distribution nozzle to the process field without passing through the gas mixture tank, said supplying the nitriding gas including activating the nitriding gas by generating plasma by use of the exciting mechanism, while controlling the first and second switching valves to be opened and closed so as to alternately and pulse-wise supply the mixture gas from the gas mixture tank and the nitriding gas from the second supply source to the process field a plurality of times, and keeping the first switching valve closed during said forming the mixture gas except for said supplying the mixture gas pulse-wise.