Etching Solutions for Cu Monolayer or Cu Molybdenum Multilayers and Method of Preparing the Same

摘要

PURPOSE: Etching solutions for Cu monolayer or Cu-molybdenum multilayers comprising deionized water and two types of additives comprising hydrogen peroxide water, organic acid, phosphate and nitrogen, and an etching method are provided. CONSTITUTION: The etching solutions comprises first additive comprising 8 to 20 wt.% of hydrogen peroxide water for the total weight of composition, 1 to 5 wt.% of organic acid for the total weight of composition, 0.2 to 5 wt.% of phosphate for the total weight of composition and 0.2 to 5 wt.% of nitrogen for the total weight of composition; second additive comprising 0.2 to 5 wt.% of nitrogen for the total weight of composition; and a balance of deionized water for the total weight of composition. The etching method comprises first step of depositing copper/molybdenum layer on a substrate; second step of selectively leaving photoresist on the copper/molybdenum layer; and third step of etching the copper/molybdenum layer using the etching solution, wherein the copper/molybdenum layer is a double film in which copper film(14) is formed on molybdenum layer(12), wherein thickness of the copper layer is thicker than that of the molybdenum layer, wherein the substrate is a glass substrate(10) for TFT LCD (thin film transistor liquid crystal display), and wherein the copper layer is a source/drain wiring.