US Patent 7915179 Insulating film forming method and substrate processing method

In a method for forming an insulating film by performing plasma nitriding process to an oxide film on a substrate and then by annealing the substrate in a process chamber (51), the substrate is annealed under a low pressure of 667 Pa or lower. The annealing is performed for 5 or 45 seconds. The plasma nitriding process is performed by microwave plasma by using a planar antenna whereupon a multitude of slot holes are formed.