Patent ID: 8486838
Filing Date: 2013-07-16
Classification: H01L,H05K

Abstract:
1. A method for forming a fine pattern using isotropic etching, the method comprising the steps of: (1) forming an etching layer made of metal on a semiconductor substrate, and coating a photoresist layer on the etching layer; (2) performing a lithography process with respect to the etching layer coated with the photoresist layer, and performing a first isotropic etching process with respect to the etching layer including a photoresist pattern formed through the lithography process; wherein the first isotropic etching process is performed until 10% to 50% of a thickness of the etching layer is etched from a top surface of the etching layer making contact with the photoresist layer; (3) depositing a passivation layer on the photoresist pattern and on a portion of the etching layer subjected to the lithography process; (4) removing a first portion of the passivation layer corresponding to a portion of the etching layer that is subject to the first isotropic etching such that a second portion of the passivation layer remains deposited on the photoresist pattern and on a portion of the etching layer undercut by the first isotropic etching; and (5) performing a second isotropic etching process with respect to the removed portion of the passivation layer such that the photoresist remains coated on the etching layer and a portion of the passivation layer remains deposited on the photoresist pattern and on the portion of the etching layer undercut by the first and second isotropic etchings.