THIN FILM TRANSISTOR ELEMENT MANUFACTURING METHOD, ORGANIC EL DISPLAY PANEL MANUFACTURING METHOD, ETCHING DEVICE AND WET ETCHING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a favorable manufacturing method of a thin film transistor having a wiring layer which is made mostly from copper and contains manganese.SOLUTION: A manufacturing method of a thin film transistor element 100 which includes on a substrate 101, a channel layer 104 which is made mostly from an oxide semiconductor and upper wiring layers 106s, 106d which are upper layers than the channel layer 104 and made mostly from copper comprises the steps of: forming an upper metal layer 106M in which a low resistance layer 106Mb made mostly from copper and a cap layer 106Mc made mostly from a manganese-containing copper alloy are laminated in this order; and performing wet etching on the upper metal layer 106M by using an etchant 113a with a manganese concentration controlled to be not less than 0 ppm and not more than 30 ppm to form upper wiring layers 106s, 106d.SELECTED DRAWING: Figure 12