Compositions for etching metal layers

Abstract

The present invention relates to a composition for etching metal films, and more specifically, to an etchant composition comprising an oxidant, an etching controller, a chelating agent, an undercut inhibitor, a copper corrosion inhibitor, a residue remover and the balance of water, for collectively wet etching metal films used as a gate electrode and a data electrode within a thin film transistor for a flat display, particularly, a single-layered film or a multilayered film consisting of one or more materials selected from copper, molybdenum, titanium and a molybdenum-titanium alloy. The composition of the present invention inhibits the rapid reaction of an oxidant and a copper ion when applied to an etching process through the use of a novel chelating agent, thereby providing an etchant with excellent lifetime and stability, an etched metal film with a gentle slope angle, suitable control of CD loss, and a good etching profile inhibiting the residue of a lower molybdenum, titanium or molybdenum-titanium alloy film. In addition, if a volatilization inhibitor is further added, precipitate and foreign matter generation is greatly reduced in etching equipment, and thus it is possible to improve productivity with respect to etching equipment operation and to reduce failure rates.

Description

Technical field [0001] The present invention relates to a metal film used to etch the gate electrode and data electrode of a thin film transistor used as a flat panel display through batch wet etching, and particularly includes a metal film selected from copper, molybdenum, titanium, and molybdenum-titanium alloys. Or multiple single-layer or multilayer film compositions. Background technique [0002] Thin film transistors are obtained by forming metal wires on a substrate. Generally speaking, a metal film is formed by physical adsorption, and then patterned and etched by exposure using a photoresist to prepare a patterned thin film. Among them, the etching process is a process in which a metal film is selectively etched according to a pattern formed in an exposure process. [0003] Since thin film transistor liquid crystal displays with better performance are required, a metal film with low resistance to fast driving is required. To meet this requirement, metal materials such a...

AI Technical Summary

Problems solved by technology

Although many improvements have been achieved regarding residue and stability issues, deposition in etch setups is still a problem

Images