Microelectronic fabrication methods using composite layers for double patterning

摘要

Some embodiments provide microelectronic fabrication methods in which a sacrificial pattern is formed on a substrate. A spacer formation layer is formed on the substrate, the spacer formation layer covering the sacrificial pattern. The spacer formation layer is etched to expose an upper surface of the sacrificial pattern and to leave at least one spacer on at least one sidewall of the sacrificial pattern. A first portion of the sacrificial pattern having a first width is removed while leaving intact a second portion of the sacrificial pattern having a second width greater than the first width to thereby form a composite mask pattern including the at least one spacer and a portion of the sacrificial layer. An underlying portion of the substrate is etched using the composite mask pattern as an etching mask.

主权项

1. A method comprising:
forming an etching target layer on a substrate comprising a cell region, a connection region, and a peripheral region; forming a sacrificial layer on the etching target layer; patterning the sacrificial layer to form a sacrificial pattern on the cell region and the connection region; forming at least one sidewall spacer on the sacrificial pattern; etching the etching target layer using the at least one sidewall spacer as an etch mask in the cell region and using the at least one sidewall spacer and the sacrificial pattern as an etch mask in the connection region to form a first pattern on the cell region and the connection region; forming a photoresist layer covering the first pattern; patterning the photoresist layer in the peripheral region to form a photoresist pattern on the peripheral region; and etching the etching target layer in the peripheral region using the photoresist pattern as an etch mask to form a second pattern in the peripheral region.