Exemplary etching methods may include flowing a fluorine-containing precursor and a hydrogen-containing precursor into a remote plasma region of a semiconductor processing chamber. The methods may include forming a plasma of the fluorine-containing precursor and the hydrogen-containing precursor to produce plasma effluents. The methods may include flowing the plasma effluents into a substrate processing region housing a substrate. The substrate may include an exposed region of a tantalum or titanium material and an exposed region of a silicon-containing material. The methods may include contacting the substrate with the plasma effluents. The methods may include removing the tantalum or titanium material selectively to the silicon-containing material. The tantalum or titanium material may be removed at a rate of at least 20:1 relative to the silicon-containing material.

Exemplary etching methods may include flowing a fluorine-containing precursor and a hydrogen-containing precursor into a remote plasma region of a semiconductor processing chamber. The methods may include forming a plasma of the fluorine-containing precursor and the hydrogen-containing precursor to produce plasma effluents. The methods may include flowing the plasma effluents into a substrate processing region housing a substrate. The substrate may include an exposed region of a tantalum or titanium material and an exposed region of a silicon-containing material. The methods may include contacting the substrate with the plasma effluents. The methods may include removing the tantalum or titanium material selectively to the silicon-containing material. The tantalum or titanium material may be removed at a rate of at least 20:1 relative to the silicon-containing material.

Methods of etching metal by depositing a material reactive with a metal to be etched and a halogen to form a volatile species and exposing the substrate to a halogen-containing gas and activation gas to etch the substrate are provided. Deposited materials may include silicon, germanium, titanium, carbon, tin, and combinations thereof. Methods are suitable for fabricating MRAM structures and may involve integrating ALD and ALE processes without breaking vacuum.

The dry etching method of the present invention etches a metal film formed on a surface of a workpiece by bringing etching gases each containing a β-diketone into contact with the metal film. The method includes: a first etching step of bringing a first etching gas containing a first β-diketone into contact with the metal film; and a second etching step of bringing a second etching gas containing a second β-diketone into contact with the metal film after the first etching step. The first β-diketone is a compound capable of forming a first complex through a reaction with the metal film. The second β-diketone is a compound capable of forming a second complex having a lower sublimation point than the first complex through a reaction with the metal film.

The dry etching method of the present invention etches a metal film formed on a surface of a workpiece by bringing etching gases each containing a β-diketone into contact with the metal film. The method includes: a first etching step of bringing a first etching gas containing a first β-diketone into contact with the metal film; and a second etching step of bringing a second etching gas containing a second β-diketone into contact with the metal film after the first etching step. The first β-diketone is a compound capable of forming a first complex through a reaction with the metal film. The second β-diketone is a compound capable of forming a second complex having a lower sublimation point than the first complex through a reaction with the metal film.

A method of removing copper oxide from copper surfaces is disclosed that comprises application of vapor generated by an ultrasonic wave nebulizer. The energized vapor droplets include water and a weak organic acid such as acetic acid, lactic acid, citric acid, uric acid, oxalic acid, or formic acid that have a vapor pressure proximate to that of water. The weak organic acid preferably has a pKa high enough to avoid Cu etching but is sufficiently acidic to remove copper oxide at a rate that is compatible with high throughput manufacturing. In one embodiment, weak acid/water vapor is applied to a substrate in a spin bowl and is followed by a deionized water rinse step in the same spin bowl. Improved wettability results in improved uniformity in subsequently plated copper films. Considerable cost savings is realized as a result of reduced chemical consumption and higher product yields.

A method of removing copper oxide from copper surfaces is disclosed that comprises application of vapor generated by an ultrasonic wave nebulizer. The energized vapor droplets include water and a weak organic acid such as acetic acid, lactic acid, citric acid, uric acid, oxalic acid, or formic acid that have a vapor pressure proximate to that of water. The weak organic acid preferably has a pKa high enough to avoid Cu etching but is sufficiently acidic to remove copper oxide at a rate that is compatible with high throughput manufacturing. In one embodiment, weak acid/water vapor is applied to a substrate in a spin bowl and is followed by a deionized water rinse step in the same spin bowl. Improved wettability results in improved uniformity in subsequently plated copper films. Considerable cost savings is realized as a result of reduced chemical consumption and higher product yields.

A method for patterning a material layer on a substrate includes forming a hard mask layer on a material layer disposed on a substrate, the material layer comprising a plurality of first layers and a plurality of second layers alternately formed over the substrate, performing a first etch process to form features in the material layer through the hard mask layer by supplying a first etching gas, and performing a second etch process to smooth sidewalls of the features formed in the material layer by suppling a second etching gas. The first etching gas is supplied continuously and the second etching gas is pulsed.

Provided are methods for etching films comprising transition metals. Certain methods involve activating a substrate surface comprising at least one transition metal, wherein activation of the substrate surface comprises exposing the substrate surface to heat, a plasma, an oxidizing environment, or a halide transfer agent to provide an activated substrate surface; and exposing the activated substrate surface to a reagent comprising a Lewis base or pi acid to provide a vapor phase coordination complex comprising one or more atoms of the transition metal coordinated to one or more ligands from the reagent. Certain other methods provide selective etching from a multi-layer substrate comprising two or more of a layer of Co, a layer of Cu and a layer of Ni.

Provided are methods for etching films comprising transition metals. Certain methods involve activating a substrate surface comprising at least one transition metal, wherein activation of the substrate surface comprises exposing the substrate surface to heat, a plasma, an oxidizing environment, or a halide transfer agent to provide an activated substrate surface; and exposing the activated substrate surface to a reagent comprising a Lewis base or pi acid to provide a vapor phase coordination complex comprising one or more atoms of the transition metal coordinated to one or more ligands from the reagent. Certain other methods provide selective etching from a multi-layer substrate comprising two or more of a layer of Co, a layer of Cu and a layer of Ni.