Patent ID: 7265013

Claim:
A structure fabrication method, comprising: providing a structure which comprises (a) a to-be-etched layer, (b) a memory region on the to-be-etched layer, (c) a positioning region on the memory region such that the memory region is sandwiched between the to-be-etched layer and the positioning region, (d) and a capping region on the positioning region such that the positioning region is sandwiched between the memory region and the capping region; indenting the positioning region so as to undercut the capping region; forming a conformal protective layer on exposed-to-ambient surfaces of the structure after said indenting is performed; removing portions of the conformal protective layer so as to expose the capping region to the surrounding ambient without exposing the memory region to the surrounding ambient; removing the capping region, after said removing the portions of the conformal protective layer is performed, so as to expose the positioning region to the surrounding ambient; removing the positioning region, after said removing the capping region is performed, so as to expose the memory region to the surrounding ambient; and directionally etching the memory region with remaining portions of the conformal protection layer serving as a blocking mask for said directionally etching the memory region, after said removing the positioning region is performed.