The disclosed and claimed subject matter relates to wet etchants exhibiting high copper and cobalt etching rates where the etching rate ratio between the two metals can be varied. The wet etchants have a composition comprising a formulation consisting of: at least one alkanolamine having at least two carbon atoms, at least one amino substituent and at least one hydroxyl substituent with the amino and hydroxyl substituents attached to two different carbon atoms; at least one pH adjuster for adjusting the pH of the formulation to between approximately 9 and approximately 12; at least one chelating agent; and water.

A method for recycling a rare earth magnet is described. The rare earth magnet has a film containing Ni on the surface thereof, and the method involves immersing the rare earth magnet in a stripping solution containing a derivative of nitrobenzene, ethylenediamine, and ammonia. This strips the Ni on the surface of the rare earth magnet without deteriorating the characteristics of the rare earth magnet, thereby improving its product yield.

A method for recycling a rare earth magnet is described. The rare earth magnet has a film containing Ni on the surface thereof, and the method involves immersing the rare earth magnet in a stripping solution containing a derivative of nitrobenzene, ethylenediamine, and ammonia. This strips the Ni on the surface of the rare earth magnet without deteriorating the characteristics of the rare earth magnet, thereby improving its product yield.

An aqueous etching composition comprising: (a) functionalized urea, biuret and guanidine derivatives and/or salts thereof selected from compounds having formulae I or II:

##STR00001## wherein X and Y are independently selected from oxygen, NRR′ and NR.sup.5, R, R′ and R.sup.5 are independently selected from R.sup.1, hydrogen, polyethylene glycols, aromatic compounds, and C.sub.1-C.sub.4 alkyl, wherein the aromatic compounds and C.sub.1-C.sub.4 alkyl optionally comprise at least one substituent selected as OR.sup.6, R.sup.6 is selected from hydrogen and C.sub.1-C.sub.4alkyl, X and Y can be identical or different; R.sup.1 and R.sup.2 are independently selected from hydrogen, alkyl compounds, amines, and nitrogen-comprising heteroaromatic compounds, R.sup.1 and R.sup.2 can be identical or different, with the proviso that R.sup.1 cannot be hydrogen, and with the proviso that in compounds having formula I R.sup.1 cannot be hydrogen or alkyl compound if X is oxygen; m is an integer from 1 to 4, and n is an integer from 0 to 8; wherein m and n can be identical or different; (b) an oxidizing agent; and wherein the composition comprises a pH from 7.1 to 14.

The present invention provides a composition having an excellent dissolving ability for a transition metal-containing substance and a method for treating a substrate. The composition according to an embodiment of the present invention contains at least one oxohalogen acid compound selected from the group consisting of hypochlorous acid, chlorous acid, chloric acid, bromic acid, and salts thereof and a compound represented by Formula (1), in which a content of the compound represented by Formula (1) is 1.0% to 25.0% by mass with respect to a total mass of the composition.

##STR00001##

The present invention provides a semiconductor wafer treatment liquid, the treatment liquid including at least one hypohalite ion, and at least one anion species selected from halate ion, halite ion and halide ion, wherein at least one of the anion species has a content of 0.30 mol/L or more and 6.00 mol/L or less relative to the treatment liquid.

The present invention provides a semiconductor wafer treatment liquid, the treatment liquid including at least one hypohalite ion, and at least one anion species selected from halate ion, halite ion and halide ion, wherein at least one of the anion species has a content of 0.30 mol/L or more and 6.00 mol/L or less relative to the treatment liquid.

The present disclosure provides improved wet etch processes and methods for etching noble metals. More specifically, the present disclosure provides various embodiments of wet etch processes and methods that utilize new etch chemistries for etching noble metals, such as ruthenium (Ru), gold (Au), platinum (Pt) and iridium (Ir), in a wet etch process. In general, the disclosed embodiments expose a noble metal surface to a first etch solution to chemically modify the noble metal surface and form a noble metal salt passivation layer, which can then be selectively dissolved in a second etch solution to etch the noble metal surface.

The present disclosure provides a new wet atomic layer etch (ALE) process for etching ruthenium. More specifically, the present disclosure provides various embodiments of methods that utilize new etch chemistries for etching ruthenium in a wet ALE process. Unlike conventional etch processes for ruthenium, the wet ALE process described herein for etching ruthenium is metal-free, cost-effective and improves surface roughness during etching.

A method for manufacturing a ruthenium wiring including (i) treating a metal surface including ruthenium using a first chemical solution including a compound having a functional group capable of coordinating to a ruthenium atom, and (ii) carrying out an etching treatment on the metal surface including ruthenium treated with the first chemical solution, using a second chemical solution.