Patent ID: 8765614
Filing Date: 2014-07-01
Classification: C23F,H01L

Abstract:
1. A method of forming a metal pattern having at least a portion thereof disposed over an active layer of a switching element, the method comprising: forming, on a base substrate having material of the active layer pre-disposed thereon, a copper-based metal layer having a predetermined thickness between about 1,500 Å and about 5,500 Å; forming a patterned photoresist layer above the copper-based metal layer; and first etching through the thickness of the un-patterned copper-based metal layer while not substantially removing an underlying active layer, the first etching simultaneously providing a sidewall in-cutting of the copper-based metal layer in accordance with a predetermined skew length, the first etching being an over-etching through said thickness that has an over-etch factor of between about 40% to about 200%, said first etching using the patterned photoresist layer as an etch stopping layer and using an etching composition including ammonium persulfate between about 0.1% by weight to about 50% by weight, an azole-based compound between about 0.01% by weight to about 5% by weight and a remainder including water, to form the metal pattern disposed over the active layer; wherein the combination of the predetermined thickness of the copper-based metal layer and the concentration of the azole-based compound are pre-selected so as to provide said non-removal of the underlying active layer and to provide said predetermined skew length.