METHOD FOR FABRICATING SEMICONDUCTOR DEVICE TO PREVENT MOBILITY FROM BEING DETERIORATED

摘要

PURPOSE: A method for fabricating a semiconductor device is provided to prevent mobility from being deteriorated by decreasing the quantity of impurities in a gate insulation layer and by reducing a leakage current. CONSTITUTION: The first insulation layer is formed on a substrate(S1). The second insulation layer is formed on the first insulation layer. A gate electrode is formed on the second insulation layer. A material for forming a layer is supplied and absorbed to the upper surface of the first insulation layer(S2). The unabsorbed material for forming the layer is purged(S3). An oxide agent is supplied to oxidize the absorbed material for forming the layer(S4). The oxide agent having not contributed to the oxidation is purged(S5). A process for forming the second insulation layer is consecutively performed during a plurality cycles. The interval of time for purging the oxide agent having not contributed to oxidation during the first predetermined cycles is longer than that for purging the oxide agent during the nest cycle.