Patent ID: 8491805
Filing Date: 2013-07-23
Classification: H01J,H01L

Abstract:
1. A semiconductor device manufacturing method comprising: a plasma etching step for etching a single etching target film formed on a substrate accommodated in a processing chamber, wherein the processing chamber includes a pressure control valve, wherein in the plasma etching step, a processing gas including a gaseous mixture containing a plurality of predetermined gases is supplied into the processing chamber, and wherein said plasma etching step includes a cycle, wherein said cycle is repeated consecutively at least three times without extinguishing a plasma generated in the processing chamber, and further wherein said cycle includes a first step in which a flow rate of at least one of the predetermined gases is set to a first value during a first time period, and said cycle further includes a second step in which the flow rate of said at least one of the predetermined gases is set to a second value that is different from the first value during a second time period; wherein the first time period and the second time period are each set to range from about 1 to 15 seconds; wherein a total flow rate of the plurality of predetermined gases in the first step and a total flow rate of the plurality of predetermined gases in the second step are set to be substantially equal to each other, or a difference between the total flow rates, if there exists, is set to range within about 10% of the larger one of the total flow rates so that a pressure variation between the first step and the second step is in a range in which the pressure control valve provided in the processing chamber is operable; and wherein a gas for facilitating etching of the single etching target film is contained in the processing gas in each of the first and the second step.