A method for etching a metal surface includes a step of contacting a metal surface with a protic compound for a first time period to produce a first modified surface. The first modified surface is contacted with a protic ligand-forming compound that reacts with the first modified surface to form a volatile metal-containing compound including a metal atom and the protic ligand-forming compound. The volatile metal-containing compound is removed from the vicinity of the metal surface.

A method for etching a metal surface includes a step of contacting a metal surface with a protic compound for a first time period to produce a first modified surface. The first modified surface is contacted with a protic ligand-forming compound that reacts with the first modified surface to form a volatile metal-containing compound including a metal atom and the protic ligand-forming compound. The volatile metal-containing compound is removed from the vicinity of the metal surface.

A method for producing a vapor deposition mask capable of satisfying both enhancement in definition and reduction in weight even when a size is increased, and a method for producing an organic semiconductor element capable of producing an organic semiconductor element with high definition are provided. A vapor deposition mask is produced by the steps of preparing a metal plate with a resin layer in which a resin layer is provided on one surface of a metal plate, forming a metal mask with a resin layer by forming a slit that penetrates through only the metal plate, for the metal plate in the metal plate with a resin layer, and thereafter, forming a resin mask by forming openings corresponding to a pattern to be produced by vapor deposition in a plurality of rows lengthwise and crosswise in the resin layer by emitting a laser from the metal mask side.

A method for producing a vapor deposition mask capable of satisfying both enhancement in definition and reduction in weight even when a size is increased, and a method for producing an organic semiconductor element capable of producing an organic semiconductor element with high definition are provided. A vapor deposition mask is produced by the steps of preparing a metal plate with a resin layer in which a resin layer is provided on one surface of a metal plate, forming a metal mask with a resin layer by forming a slit that penetrates through only the metal plate, for the metal plate in the metal plate with a resin layer, and thereafter, forming a resin mask by forming openings corresponding to a pattern to be produced by vapor deposition in a plurality of rows lengthwise and crosswise in the resin layer by emitting a laser from the metal mask side.

Disclosed is a dry etching method for etching a metal film on a substrate with the use of an etching gas, wherein the etching gas contains a -diketone and first and second additive gases; wherein the metal film contains a metal element capable of forming a complex with the -diketone; wherein the first additive gas is at least one kind of gas selected from the group consisting of NO, NO.sub.2, O.sub.2 and O.sub.3; wherein the second additive gas is at least one kind of gas selected from the group consisting of H.sub.2O and H.sub.2O.sub.2; wherein the amount of the -diketone contained is 10 vol % to 90 vol % relative to the etching gas; and wherein the amount of the second additive gas contained is 0.1 vol % to 15 vol % relative to the etching gas. The etching rate of the metal film is increased by this etching method.

Disclosed is a dry etching method for etching a metal film on a substrate with the use of an etching gas, wherein the etching gas contains a -diketone and first and second additive gases; wherein the metal film contains a metal element capable of forming a complex with the -diketone; wherein the first additive gas is at least one kind of gas selected from the group consisting of NO, NO.sub.2, O.sub.2 and O.sub.3; wherein the second additive gas is at least one kind of gas selected from the group consisting of H.sub.2O and H.sub.2O.sub.2; wherein the amount of the -diketone contained is 10 vol % to 90 vol % relative to the etching gas; and wherein the amount of the second additive gas contained is 0.1 vol % to 15 vol % relative to the etching gas. The etching rate of the metal film is increased by this etching method.

A cleaning method for a by-product including a refractory material or a metal compound includes a reforming process and an etching process. In the reforming process, a surface of the by-product is reformed using nitrogen-containing gas and hydrogen-containing gas. In the etching process, the reformed surface is etched using halogen-containing gas and inert gas.

A cleaning method for a by-product including a refractory material or a metal compound includes a reforming process and an etching process. In the reforming process, a surface of the by-product is reformed using nitrogen-containing gas and hydrogen-containing gas. In the etching process, the reformed surface is etched using halogen-containing gas and inert gas.

A method includes depositing an etch stop layer over a first conductive feature, performing a first treatment to amorphize the etch stop layer, depositing a dielectric layer over the n etch stop layer, etching the dielectric layer to form an opening, etching-through the etch stop layer to extend the opening into the etch stop layer, and filling the opening with a conductive material to form a second conductive feature.

A method includes depositing an etch stop layer over a first conductive feature, performing a first treatment to amorphize the etch stop layer, depositing a dielectric layer over the n etch stop layer, etching the dielectric layer to form an opening, etching-through the etch stop layer to extend the opening into the etch stop layer, and filling the opening with a conductive material to form a second conductive feature.