Methods of forming impurity containing insulating films and flash memory devices including the same

摘要

Methods of forming an insulating film include forming an insulating film on a substrate. A first impurity is injected into the insulating film using a thermal process under a first set of processing conditions to form a first impurity concentration peak in a lower portion of the insulating film. A second impurity is injected into the insulating film using the thermal process under a second set of processing conditions, different from the first set of processing conditions, to form a second impurity concentration peak in an upper portion of the insulating film. Injecting the first impurity and injecting the second impurity may be carried out without using plasma and the first impurity concentration peak may be higher than the second impurity concentration peak.