The present disclosure provides a system for etching an exposed material on a substrate disposed within a process chamber using a hybrid atomic layer etching (ALE) process that combines a gas-phase surface modification step with a liquid-phase dissolution step within the same process chamber. In the hybrid ALE process disclosed herein, a gas-phase reactant is used to modify an exposed surface of the material to create a modified surface layer, and one or more liquid-phase reactants are used to selectively dissolve the modified surface layer without dissolving the material underlying the modified surface layer. Once the modified surface layer is selectively dissolved, the substrate may be dried and the gas-phase surface modification and liquid-phase dissolution steps may be repeated for one or more ALE cycles until a desired amount of the material is etched.

Atomic layer etching (ALE) processes are disclosed. In some embodiments, the methods comprise at least one etch cycle in which the substrate is alternately and sequentially exposed to a first vapor phase non-metal halide reactant and a second vapor phase halide reactant. In some embodiments both the first and second reactants are chloride reactants. In some embodiments the first reactant is fluorinating gas and the second reactant is a chlorinating gas. In some embodiments a thermal ALE cycle is used in which the substrate is not contacted with a plasma reactant.

Atomic layer etching (ALE) processes are disclosed. In some embodiments, the methods comprise at least one etch cycle in which the substrate is alternately and sequentially exposed to a first vapor phase non-metal halide reactant and a second vapor phase halide reactant. In some embodiments both the first and second reactants are chloride reactants. In some embodiments the first reactant is fluorinating gas and the second reactant is a chlorinating gas. In some embodiments a thermal ALE cycle is used in which the substrate is not contacted with a plasma reactant.

Vapor deposition methods for depositing transition metal dichalcogenide (TMDC) films, such as rhenium sulfide thin films, are provided. In some embodiments TMDC thin films are deposited using a deposition cycle in which a substrate in a reaction space is alternately and sequentially contacted with a vapor phase transition metal precursor, such as a transition metal halide, a reactant comprising a reducing agent, such as NH.sub.3 and a chalcogenide precursor. In some embodiments rhenium sulfide thin films are deposited using a vapor phase rhenium halide precursor, a reducing agent and a sulfur precursor. The deposited TMDC films can be etched by chemical vapor etching using an oxidant such as O.sub.2 as the etching reactant and an inert gas such as N.sub.2 to remove excess etching reactant. The TMDC thin films may find use, for example, as 2D materials.

Vapor deposition methods for depositing transition metal dichalcogenide (TMDC) films, such as rhenium sulfide thin films, are provided. In some embodiments TMDC thin films are deposited using a deposition cycle in which a substrate in a reaction space is alternately and sequentially contacted with a vapor phase transition metal precursor, such as a transition metal halide, a reactant comprising a reducing agent, such as NH.sub.3 and a chalcogenide precursor. In some embodiments rhenium sulfide thin films are deposited using a vapor phase rhenium halide precursor, a reducing agent and a sulfur precursor. The deposited TMDC films can be etched by chemical vapor etching using an oxidant such as O.sub.2 as the etching reactant and an inert gas such as N.sub.2 to remove excess etching reactant. The TMDC thin films may find use, for example, as 2D materials.

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 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 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.

Thermal atomic layer etching processes are disclosed. In some embodiments, the methods comprise at least one etch cycle in which the substrate is alternately and sequentially exposed to a first vapor phase halide reactant and a second vapor halide reactant. In some embodiments, the first reactant may comprise an organic halide compound. During the thermal ALE cycle, the substrate is not contacted with a plasma reactant.

Thermal atomic layer etching processes are disclosed. In some embodiments, the methods comprise at least one etch cycle in which the substrate is alternately and sequentially exposed to a first vapor phase halide reactant and a second vapor halide reactant. In some embodiments, the first reactant may comprise an organic halide compound. During the thermal ALE cycle, the substrate is not contacted with a plasma reactant.

Provided is a sensor including a substrate that includes a major surface, a sensor part that includes a gas flow path formed of a porous material, and at least one of a heater or a temperature sensor. The heater is capable of heating the sensor part, the temperature sensor is capable of measuring temperature of the sensor part, the sensor part and the at least one of the heater or the temperature sensor are stacked over the major surface, the at least one of the heater or the temperature sensor is an interconnect having forward tapered side surfaces, and the at least one of the heater or the temperature sensor includes a metal interconnect layer, and the forward tapered side surfaces of the interconnect overlap with the gas flow path in plan view of the major surface.