Patent ID: 8802537
Filing Date: 2014-08-12
Classification: H01L

Abstract:
1. A method for forming a memory device, the method comprising: forming a barrier oxide layer over a substrate; forming a nitride layer over the barrier oxide layer; etching the nitride layer, the barrier oxide layer and the substrate to form a trench, pre-cleaning the memory device to prepare an exposed surface of the sidewalls of the trench for oxide formation thereon, trimming, after pre-cleaning the memory device, the nitride layer to remove portions of the nitride layer on opposite sides of the trench and to expose second portions of the barrier oxide layer on the opposite sides of the trench, forming a liner oxide layer on the sidewalls of the trench; filling the trench with a field oxide material over the liner oxide layer; planarizing the field oxide material to form a planar top surface that is aligned with a top surface of the trimmed nitride layer; stripping the trimmed nitride layer to form a mesa from the field oxide material, cleaning the memory device to strip the barrier oxide layer and to remove portions of the field oxide layer,