Patent ID: 9165784
Filing Date: 2015-10-20
Classification: H01L

Abstract:
1. A substrate processing method for forming a hole or a trench having a high aspect ratio comprising: etching an oxide film formed on a wafer corresponding to an opening of a mask layer made of silicon using plasma generated from a processing gas containing a fluorocarbon gas and a hydrocarbon gas, the etching being performed in such a way that a depth of the hole or the trench is less than a predetermined depth; ashing a fluorocarbon-based reactive product generated in the hole or the trench and a hydrocarbon-based reactive product generated on the mask layer during the etching using plasma generated from a processing gas containing an oxygen gas; and repeating the etching of the oxide film on the wafer, and the ashing of the fluorocarbon-based reactive product generated in the hole or the trench and the hydrocarbon-based reactive product generated on the mask layer sequentially for a plurality of times using the same mask layer so that the depth of the hole or the trench reaches the predetermined depth by using the same mask layer.