Patent ID: 7261829

Claim:
Method for masking first recesses ( 1 ) in a structure ( 4 ) having webs ( 4 ) with a high aspect ratio, comprising a set of recesses ( 1 , 2 ) having different aspect ratios, in particular a semiconductor structure, having the following steps: a filling layer ( 5 ) is applied to the structure ( 1 , 2 , 4 ), with the filling layer ( 5 ) being applied over a fixed distance beyond the webs ( 4 ) in such a way that a cavity ( 6 ) is formed in first recesses ( 1 ) having a high aspect ratio, the filling layer ( 5 ) is removed by means of a planar removal process into the area of the cavity ( 6 ) with the filling layer ( 5 ) being removed to a defined distance above the surface of the webs ( 4 ), the filling layer ( 5 ) is removed in an etching process, with the etching process also attacking in the cavity ( 6 ) and, owing to the cavity ( 6 ), the filling layer ( 5 ) being removed more quickly from the first recess ( 1 ) than from recesses ( 2 ) without a cavity ( 6 ), and with the etching process being stopped after removal of the filling layer ( 5 ) from the first recess ( 1 ), with the defined distance being chosen such that the webs ( 4 ) are not underetched in the area of a recess ( 2 ) with a low aspect ratio during the etching process.