Disclosed are apparatuses and methods for performing atomic layer etching. A method may include modifying one or more surface layers of material on the substrate and exposing the one or more modified surface layers on the substrate to an electron source thereby removing, without using a plasma, the one or more modified surface layers on the substrate. An apparatus may include a processing chamber, a process gas unit, an electron source, and a controller with instructions configured to cause the process gas unit to flow a first process gas to a substrate in a chamber interior, the first process gas is configured to modify one or more layers of material on the substrate, and to cause the electron source to generate electrons and expose the one or more modified surface layers on the substrate to the electrons, the one or more modified surface layers being removed, without using a plasma.

A metal removal method which includes: a reaction step of bringing a treatment gas containing a fluorine-containing interhalogen compound and a metal-containing material containing a metal element into contact with each other to generate metal fluoride which is a reaction product of the fluorine-containing interhalogen compound and the metal element; and a volatilization step of heating the metal fluoride under an inert gas atmosphere or in a vacuum environment for volatilization. The metal element is at least one kind selected from iron, cobalt, nickel, selenium, molybdenum, rhodium, palladium, tungsten, rhenium, iridium, and platinum. Also disclosed is a dry etching method using the metal removal method and a production method for a semiconductor element using the dry etching method.

Exemplary methods of etching may include flowing a fluorine-containing precursor and a secondary gas into a processing region of a semiconductor processing chamber. The secondary gas may be or include oxygen or nitrogen. A flow rate ratio of the fluorine-containing precursor to the secondary gas may be greater than or about 1:1. The methods may include contacting a substrate with the fluorine-containing precursor and the secondary gas. The substrate may include an exposed metal. The substrate may define a high aspect-ratio structure. The methods may include etching the exposed metal within the high aspect-ratio structure.

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.

In accordance with some embodiments, conductive material is removed from over a first plurality of fins and second plurality of fins, wherein the first plurality of fins is located within a small gate length region and the second plurality of fins is located in a large gate length region. The removal is performed by initially performed a dry etch with a low pressure and a high flow rate of at least one etchant, which causes the conductive material to have a larger thickness over the second plurality of fins than over the first plurality of fins. As such, when a wet etch is utilized to remove a remainder of the conductive material, dielectric material between the second plurality of fins and the conductive material is not damaged.

The present invention relates to an electrical assembly which has a conformal coating, wherein said conformal coating is obtainable by a method which comprises: (a) plasma polymerization of a compound of formula (I) and a fluorohydrocarbon, wherein the molar ratio of the compound of formula (I) to the fluorohydrocarbon is from 5:95 to 50:50, and deposition of the resulting polymer onto at least one surface of the electrical assembly: wherein: R.sub.1 represents C.sub.1-C.sub.3 alkyl or C.sub.2-C.sub.3 alkenyl; R.sub.2 represents hydrogen, C.sub.1-C.sub.3 alkyl or C.sub.2-C.sub.3 alkenyl; R.sub.3 represents hydrogen, C.sub.1-C.sub.3 alkyl or C.sub.2-C.sub.3 alkenyl; R.sub.4 represents hydrogen, C.sub.1-C.sub.3 alkyl or C.sub.2-C.sub.3 alkenyl; R.sub.5 represents hydrogen, C.sub.1-C.sub.3 alkyl or C.sub.2-C.sub.3 alkenyl; and R.sub.6 represents hydrogen, C.sub.1-C.sub.3 alkyl or C.sub.2-C.sub.3 alkenyl, and (b) plasma polymerization of a compound of formula (I) and deposition of the resulting polymer onto the polymer formed in step (a).

##STR00001##

Apparatuses suitable for etching substrates at various pressure regimes are described herein. Apparatuses include a process chamber including a movable pedestal capable of being positioned at a raised position or a lowered position, showerhead, and optional plasma generator. Apparatuses may be suitable for etching non-volatile metals using a treatment while the movable pedestal is in the lowered position and a high pressure exposure to organic vapor while the movable pedestal is in the raised position.

A cleaning composition for removing plasma etching residue and/or ashing residue formed above a semiconductor substrate is provided that includes (component a) water, (component b) a hydroxylamine and/or a salt thereof, (component c) a basic organic compound, and (component d) an organic acid and has a pH of 7 to 9. There are also provided a cleaning process and a process for producing semiconductor device employing the cleaning composition.

The present invention provides a barrier layer removal method, wherein the barrier layer includes at least one layer of ruthenium or cobalt, the method comprising: removing the barrier layer including ruthenium or cobalt formed on non-recessed areas of a semiconductor structure by thermal flow etching. The present invention further provides a semiconductor structure forming method, comprising: providing a semiconductor structure which includes a dielectric layer, a hard mask layer formed on the dielectric layer, recessed areas formed on the hard mask layer and the dielectric layer, a barrier layer including at least one layer of ruthenium or cobalt formed on the hard mask layer, sidewalls of the recessed areas and bottoms of the recessed areas, a metal layer formed on the barrier layer and filling the recessed areas; removing the metal layer formed on the non-recessed areas and the metal in the recessed areas, and remaining a certain amount of metal in the recessed areas; removing the barrier layer including ruthenium or cobalt formed on the non-recessed areas, and the hard mask layer by thermal flow etching.

Methods for evaluating synergy of modification and removal operations for a wide variety of materials to determine process conditions for self-limiting etching by atomic layer etching are provided herein. Methods include determining the surface binding energy of the material, selecting a modification gas for the material where process conditions for modifying a surface of the material generate energy less than the modification energy and greater than the desorption energy, selecting a removal gas where process conditions for removing the modified surface generate energy greater than the desorption energy to remove the modified surface but less than the surface binding energy of the material to prevent sputtering, and calculating synergy to maximize the process window for atomic layer etching.