Method for etching of metal
AssigneeTokyo Electron Limited
InventorsSergey Voronin, Qi Wang, Christopher Netzband, Gabriel Gibney, Sang Cheol Han, Peter Biolsi, Arkalgud Sitaram, Christophe Vallee
Life of this patent
Estimating the term…
Abstract
A method of etching a metal includes performing at least two cycles of an etch process. A cycle of the etch process includes: performing a surface modification on an exposed surface of a metal layer over a substrate, performing a hydrogen treatment on the metal layer, and performing a cleaning treatment on the metal layer. The hydrogen treatment forms a layer of reaction products on the metal layer. The cleaning treatment removes the layer of reaction products.
Claims20
A method of etching a metal, the method comprising:
- performing at least two cycles of an etch process, wherein each cycle comprises:
- performing a surface modification on an exposed surface of a metal layer of a substrate, the metal layer and a dielectric layer of the substrate having a coplanar top surface;
- performing a hydrogen treatment on the metal layer, wherein the hydrogen treatment forms a layer of reaction products on the metal layer;
- and
- performing a cleaning treatment on the metal layer, wherein the cleaning treatment removes the layer of reaction products.
A method of smoothing a surface, the method comprising:
- providing a substrate, the substrate being planarized and containing a metal layer and a dielectric layer in the same horizontal plane, the metal layer having a rough or oxidized surface;
- and
- performing one or more cycles of a smoothing process, wherein each cycle comprises:
- exposing the rough or oxidized surface to a plasma-excited H2 gas, wherein the plasma-excited H2 gas chemically reduces the oxidized surface of the metal layer and forms a layer of reaction products on the metal layer;
- and
- exposing the rough or oxidized surface to a plasma-excited Ar gas, wherein the plasma-excited Ar gas removes the layer of reaction products overlying the metal layer, wherein kinetic energy of the plasma-excited Ar gas is at or below a sputtering threshold for removing metal from the metal layer.
A method of etching a metal, the method comprising:
- exposing a metal layer of a substrate to a surface modifying gas, the substrate being planarized and containing the metal layer and a dielectric layer in a same horizontal plane, the surface modifying gas oxidizing a surface of the metal layer;
- exposing the metal layer to a plasma-excited H2 gas, the plasma-excited H2 gas chemically reducing the oxidized surface of the metal layer and forming a layer of metal-containing reaction products on the metal layer;
- and
- exposing the metal layer to a plasma-excited Ar gas, the plasma-excited Ar gas removing the layer of metal-containing reaction products overlying the metal layer.
Dependencies are inferred from the claim text.