First, an ion beam is applied to a workpiece to form a tapered hole the side wall of which is inclined. Next, the application of the ion beam is stopped, and then a material gas is introduced from the gas source to the upper surface of the workpiece from an oblique direction to cause gas molecules to be adsorbed to the upper surface of the workpiece and to the upper portion of the side wall of the hole. Next, introduction of the material gas is stopped, and then the ion beam is applied again to the region of the workpiece where the hole is formed. As a result, at the upper portion of the side wall of the hole, film formation occurs using the gas molecules as the material adsorbed to the side wall of the hole, and, at the bottom portion of the hole, etching of the workpiece occurs.

Embodiments disclosed herein generally relate to methods and apparatus for processing of the bottom surface of a substrate to counteract thermal stresses thereon. Correcting strains are applied to the bottom surface of the substrate which compensate for undesirable strains and distortions on the top surface of the substrate. Specifically designed films may be formed on the back side of the substrate by any combination of deposition, implant, thermal treatment, and etching to create strains that compensate for unwanted distortions of the substrate. In some embodiments, localized strains may be introduced by locally altering the hydrogen content of a silicon nitride film or a carbon film, among other techniques. Structures may be formed by printing, lithography, or self-assembly techniques. Treatment of the layers of film is determined by the stress map desired and includes annealing, implanting, melting, or other thermal treatments.

First, an ion beam is applied to a workpiece to form a tapered hole the side wall of which is inclined. Next, the application of the ion beam is stopped, and then a material gas is introduced from the gas source to the upper surface of the workpiece from an oblique direction to cause gas molecules to be adsorbed to the upper surface of the workpiece and to the upper portion of the side wall of the hole. Next, introduction of the material gas is stopped, and then the ion beam is applied again to the region of the workpiece where the hole is formed. As a result, at the upper portion of the side wall of the hole, film formation occurs using the gas molecules as the material adsorbed to the side wall of the hole, and, at the bottom portion of the hole, etching of the workpiece occurs.

As etching processes become more aggressive, increased etch resistivity of the hard mask is desirable. Methods of modulating the etch rate of the mask and optionally the underlying material are disclosed. An etch rate modifying species is implanted into the hard mask after the mask etching process is completed. This etch rate modifying species increases the difference between the etch rate of the mask and the etch rate of the underlying material to help preserve the integrity of the mask during a subsequent etching process. In some embodiments, the etch rate of the mask is decreased by the etch rate modifying species. In certain embodiments, the etch rate of the underlying material is increased by the etch rate modifying species.

Provided herein are methods of atomic layer etching (ALE) of metals including tungsten (W) and cobalt (Co). The methods disclosed herein provide precise etch control down to the atomic level, with etching a low as 1 ? to 10 ? per cycle in some embodiments. In some embodiments, directional control is provided without damage to the surface of interest. The methods may include cycles of a modification operation to form a reactive layer, followed by a removal operation to etch only this modified layer. The modification is performed without spontaneously etching the surface of the metal.

Embodiments disclosed herein generally relate to methods and apparatus for processing of the bottom surface of a substrate to counteract thermal stresses thereon. Correcting strains are applied to the bottom surface of the substrate which compensate for undesirable strains and distortions on the top surface of the substrate. Specifically designed films may be formed on the back side of the substrate by any combination of deposition, implant, thermal treatment, and etching to create strains that compensate for unwanted distortions of the substrate. In some embodiments, localized strains may be introduced by locally altering the hydrogen content of a silicon nitride film or a carbon film, among other techniques. Structures may be formed by printing, lithography, or self-assembly techniques. Treatment of the layers of film is determined by the stress map desired and includes annealing, implanting, melting, or other thermal treatments.

As etching processes become more aggressive, increased etch resistivity of the hard mask is desirable. Methods of modulating the etch rate of the mask and optionally the underlying material are disclosed. An etch rate modifying species is implanted into the hard mask after the mask etching process is completed. This etch rate modifying species increases the difference between the etch rate of the mask and the etch rate of the underlying material to help preserve the integrity of the mask during a subsequent etching process. In some embodiments, the etch rate of the mask is decreased by the etch rate modifying species. In certain embodiments, the etch rate of the underlying material is increased by the etch rate modifying species.

As etching processes become more aggressive, increased etch resistivity of the hard mask is desirable. Methods of modulating the etch rate of the mask and optionally the underlying material are disclosed. An etch rate modifying species is implanted into the hard mask after the mask etching process is completed. This etch rate modifying species increases the difference between the etch rate of the mask and the etch rate of the underlying material to help preserve the integrity of the mask during a subsequent etching process. In some embodiments, the etch rate of the mask is decreased by the etch rate modifying species. In certain embodiments, the etch rate of the underlying material is increased by the etch rate modifying species.

As etching processes become more aggressive, increased etch resistivity of the hard mask is desirable. Methods of modulating the etch rate of the mask and optionally the underlying material are disclosed. An etch rate modifying species is implanted into the hard mask after the mask etching process is completed. This etch rate modifying species increases the difference between the etch rate of the mask and the etch rate of the underlying material to help preserve the integrity of the mask during a subsequent etching process. In some embodiments, the etch rate of the mask is decreased by the etch rate modifying species. In certain embodiments, the etch rate of the underlying material is increased by the etch rate modifying species.

Provided herein are methods of atomic layer etching (ALE) of metals including tungsten (W) and cobalt (Co). The methods disclosed herein provide precise etch control down to the atomic level, with etching a low as 1 to 10 per cycle in some embodiments. In some embodiments, directional control is provided without damage to the surface of interest. The methods may include cycles of a modification operation to form a reactive layer, followed by a removal operation to etch only this modified layer. The modification is performed without spontaneously etching the surface of the metal.