A wet etching method is provided in the present disclosure. The method includes providing a substrate, where a layer to-be-etched is on a surface of the substrate; and performing etching treatments on the layer to-be-etched till a thickness of the layer to-be-etched reaches a target thickness. Each etching treatment includes performing a first etching process, where the substrate is at a first rotation speed; after the first etching process, performing a second etching process, where a rotation speed of the substrate is reduced from the first rotation speed to a second rotation speed, and a liquid film of a chemical solution on the surface of the substrate is increased to a first thickness; and after the second etching process, performing a third etching process, where the substrate is at a third rotation speed, and the third rotation speed is lower than or equal to the first rotation speed.

A wet etching method is provided in the present disclosure. The method includes providing a substrate, where a layer to-be-etched is on a surface of the substrate; and performing etching treatments on the layer to-be-etched till a thickness of the layer to-be-etched reaches a target thickness. Each etching treatment includes performing a first etching process, where the substrate is at a first rotation speed; after the first etching process, performing a second etching process, where a rotation speed of the substrate is reduced from the first rotation speed to a second rotation speed, and a liquid film of a chemical solution on the surface of the substrate is increased to a first thickness; and after the second etching process, performing a third etching process, where the substrate is at a third rotation speed, and the third rotation speed is lower than or equal to the first rotation speed.

A method is described for method for patterning a metal layer interfaced with a transparent conductive film, in which the method comprises contacting a structure through a patterned mask with an etching solution comprising Fe.sup.+3 ions, wherein the structure comprises the metal layer comprising copper, nickel, aluminum or alloys thereof covering at least partially a transparent conductive film with conductive elements comprising silver, to expose a portion of the transparent conductive film. Etching solutions and the etched structures are also described.

A method is described for method for patterning a metal layer interfaced with a transparent conductive film, in which the method comprises contacting a structure through a patterned mask with an etching solution comprising Fe.sup.+3 ions, wherein the structure comprises the metal layer comprising copper, nickel, aluminum or alloys thereof covering at least partially a transparent conductive film with conductive elements comprising silver, to expose a portion of the transparent conductive film. Etching solutions and the etched structures are also described.

Polishing compositions comprising ceria coated silica particles and organic acids having one selected from the group consisting of sulfonic acid group, phosphonic acid group, pyridine compound, and combinations thereof, with pH between 5 and 10 and electrical conductivity between 0.2 and 10 millisiemens per centimeter provide very high silicon oxide removal rates for advanced semiconductor device manufacturing.

An etchant composition and a method of fabricating a semiconductor device, the composition including an inorganic acid; about 0.01 parts by weight to about 0.5 parts by weight of colloidal silica; about 0.01 parts by weight to about 30 parts by weight of an ammonium-based additive; and about 20 parts by weight to about 50 parts by weight of a solvent, all parts by weight being based on 100 parts by weight of the inorganic acid.

An etchant composition and a method of fabricating a semiconductor device, the composition including an inorganic acid; about 0.01 parts by weight to about 0.5 parts by weight of colloidal silica; about 0.01 parts by weight to about 30 parts by weight of an ammonium-based additive; and about 20 parts by weight to about 50 parts by weight of a solvent, all parts by weight being based on 100 parts by weight of the inorganic acid.

A thin film etchant composition for preventing re-adsorption of an etched metal and uniformly etching a thin film is provided. The thin film etchant composition includes about 43 wt % to about 46 wt % of phosphoric acid, about 5 wt % to about 8 wt % of nitric acid, about 10 wt % to about 17 wt % of acetic acid, about 1 wt % to about 3 wt % of iron nitrate, about 0.7 wt % to about 1.5 wt % of phosphate, and deionized water as a remaining amount based on a total weight of the thin film etchant composition.

A thin film etchant composition for preventing re-adsorption of an etched metal and uniformly etching a thin film is provided. The thin film etchant composition includes about 43 wt % to about 46 wt % of phosphoric acid, about 5 wt % to about 8 wt % of nitric acid, about 10 wt % to about 17 wt % of acetic acid, about 1 wt % to about 3 wt % of iron nitrate, about 0.7 wt % to about 1.5 wt % of phosphate, and deionized water as a remaining amount based on a total weight of the thin film etchant composition.

A patterning sheet, or the like, is suitable when a complex etching target is to be etched in a simple manner to produce an etched structure. This patterning sheet comprises a base sheet formed from an etching-solution permeable first polymer, and particles dispersed in the base sheet and formed from a second polymer, which absorbs and holds the etching solution.