Etchant and array substrate having copper lines etched by the etchant

• Main Authors: Jo, Gyoo-Chul, Chae, Ki-Sung
• Format: Patent
• Language: English
• Published: 24.08.2004

The present invention claims the benefit of Korean Patent Application No. 2000-79355, filed in Korea on Dec. 20, 2000, which is hereby incorporated by reference. A method of forming an array substrate for use in a thin film transistor liquid crystal display (TFT-LCD) device includes forming a first metal layer on a substrate, patterning the first metal layer to form a gate line and a gate electrode extended from the gale line, forming a gate insulation layer on the substrate to cover the patterned first metal layer, forming an active layer on the gate insulation layer and over the gate electrode, forming an ohmic contact layer on the active layer, forming a second metal layer on the gate insulation layer to rover the ohmic contact layer and the active layer, forming a third copper metal layer on the second metal layer, simultaneously patterning the second metal layer and the third copper metal layer to form a double-layered data line, a double-layered source electrode and a double-layered drain electrode using an etchant that includes hydrogen peroxide (HO), a HOstabilizer, and a neutral salt, and forming a pixel electrode contacting the double-layered drain electrode.