BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for treating a substrate, a method for manufacturing a semiconductor device, and a kit for treating a substrate.

2. Description of the Related Art

As the miniaturization of semiconductor products progresses, there is an increasing demand for performing a step of removing unnecessary transition metal-containing substances on a substrate in a semiconductor device manufacturing process with high efficiency.

JP4510979B discloses “method of using a remover of ruthenium or ruthenium oxide, including removal of ruthenium or ruthenium oxide attached to a silicon substrate by using a remover containing (a) ammonium cerium (IV) nitrate and (b) one acid or two or more acids selected from the group consisting of nitric acid, perchloric acid, and acetic acid, in which a content of (a) component is 5% to 35% by mass, and a content of (b) component is 1% to 30% by mass (claim1)”.

SUMMARY OF THE INVENTION

In recent years, it has been pointed out that impurities present on a substrate adversely affect the performance of a semiconductor device manufactured using the substrate, and thus the amount of impurities present on the surface of the substrate has been required to be reduced.

The inventors of the present invention examined the treatment of removing transition metal-containing substances by using the method disclosed in JP4510979B. As a result, it has been confirmed that the amount of cerium remaining as impurities on the surface of the treated substrate tends to be too large.

Therefore, an object of the present invention is to provide a method for treating a substrate, which can remove transition metal-containing substances on a substrate with high efficiency while inhibiting cerium from remaining on the surface of the treated substrate.

Another object of the present invention is to provide a method for manufacturing a semiconductor device including the method for treating a substrate, and a kit for treating a substrate that is applicable to the method for treating a substrate.

In order to achieve the above objects, the inventors of the present invention conducted intensive examinations. As a result, the inventors have found that the objects can be achieved by a method having a step A of removing a transition metal-containing substance on a substrate by using a chemical solution including a cerium compound and the like and a step B of performing a rinsing treatment on the substrate by using a specific rinsing solution, and have accomplished the present invention.

That is, the inventors have found that the above objects can be achieved by the following constitution.

[1] A method for treating a substrate, including

a step A of removing a transition metal-containing substance on a substrate by using a chemical solution, which includes a cerium compound and one or more pH adjusters selected from the group consisting of nitric acid, perchloric acid, ammonia, and sulfuric acid,

for the substrate having the transition metal-containing substance, and

a step B of performing a rinsing treatment on the substrate obtained by the step A by using one or more rinsing solutions selected from the group consisting of a solution including hydrogen peroxide and an acidic aqueous solution which is other than hydrofluoric acid, nitric acid, an aqueous perchloric acid solution, an aqueous oxalic acid solution, and a mixed aqueous solution of these and does not include hydrogen peroxide.

[2] The method for treating a substrate described in [1], in which the cerium compound is one or more kinds of compounds selected from the group consisting of cerium nitrate salts and cerium sulfate salts.

[3] The method for treating a substrate described in [1] or [2], in which the cerium compound is one or more kinds of compounds selected from the group consisting of ammonium cerium (IV) nitrate and ammonium cerium (IV) sulfate.

[4] The method for treating a substrate described in any one of [1] to [3], in which the cerium compound is ammonium cerium (IV) nitrate.

[5] The method for treating a substrate described in any one of [1] to [4], in which the solution including hydrogen peroxide is a solution selected from the group consisting of aqueous hydrogen peroxide, a mixed solution of hydrofluoric acid and aqueous hydrogen peroxide, a mixed solution of sulfuric acid and aqueous hydrogen peroxide, a mixed solution of aqueous ammonia and aqueous hydrogen peroxide, and a mixed solution of hydrochloric acid and aqueous hydrogen peroxide.

[6] The method for treating a substrate described in any one of [1] to [5], in which the acidic aqueous solution, which is other than hydrofluoric acid, nitric acid, an aqueous perchloric acid solution, an aqueous oxalic acid solution, and a mixed aqueous solution of these and does not include hydrogen peroxide, is an acidic aqueous solution selected from the group consisting of sulfuric acid, phosphoric acid, aqueous carbon dioxide, aqueous ozone, aqueous hydrogen, an aqueous citric acid solution, an aqueous periodic acid solution, an aqueous hypochlorous acid solution, and aqua regia.

[7] The method for treating a substrate described in any one of [1] to [6], in which a pH of the chemical solution is −1.0 to 4.0.

[8] The method for treating a substrate described in any one of [1] to [7], in which a content of the cerium compound is equal to or greater than 5% by mass with respect to a total mass of the chemical solution.

[9] The method for treating a substrate described in any one of [1] to [8], in which a content of the cerium compound is equal to or smaller than 30% by mass with respect to a total mass of the chemical solution.

[10] The method for treating a substrate described in any one of [1] to [9], in which the pH adjuster includes nitric acid.

[11] The method for treating a substrate described in [10], in which a content of the nitric acid is equal to or greater than 1% by mass with respect to a total mass of the chemical solution.

[12] The method for treating a substrate described in [10] or [11], in which a content of the nitric acid is equal to or smaller than 30% by mass with respect to a total mass of the chemical solution.

[13] The method for treating a substrate described in any one of [1] to [12], in which a temperature of the chemical solution is equal to or higher than 35° C.

[14] The method for treating a substrate described in any one of [1] to [13], in which a temperature of the chemical solution is equal to or lower than 60° C.

[15] The method for treating a substrate described in any one of [1] to [14], in which the rinsing solution is a mixed solution of sulfuric acid and aqueous hydrogen peroxide that has a temperature of 90 to 250° C., or one or more solutions that are selected from the group consisting of the solution including hydrogen peroxide other than the mixed solution of sulfuric acid and aqueous hydrogen peroxide and the acidic aqueous solution and have a temperature of 15° C. to 70° C.

[16] The method for treating a substrate described in any one of [1] to [15], in which the transition metal-containing substance includes at least one kind of metal selected from the group consisting of Ru, Ti, Ta, Co, Cr, Hf, Os, Pt, Ni, Mn, Cu, Zr, Mo, La, W, and Ir.

[17] The method for treating a substrate described in [16], in which the transition metal-containing substance includes a Ru-containing substance.

[18] The method for treating a substrate described in any one of [1] to [17], in which the step A is a step A1 of performing a recess etching treatment on transition metal-containing wiring disposed on a substrate by using the chemical solution, a step A2 of removing a transition metal-containing film at an outer edge portion of a substrate, on which the transition metal-containing film is disposed, by using the chemical solution, a step A3 of removing a transition metal-containing substance attached to a back surface of a substrate, on which a transition metal-containing film is disposed, by using the chemical solution, a step A4 of removing a transition metal-containing substance on a substrate, which has undergone dry etching, by using the chemical solution, or a step A5 of removing a transition metal-containing substance on a substrate, which has undergone a chemical mechanical polishing treatment, by using the chemical solution.

[19] The method for treating a substrate described in [18] that has the step A1 as the step A, further including:

a step Ab of treating the substrate obtained by the step A1 by using a solution selected from the group consisting of a mixed solution of hydrofluoric acid and aqueous hydrogen peroxide, a mixed solution of sulfuric acid and aqueous hydrogen peroxide, a mixed solution of aqueous ammonia and aqueous hydrogen peroxide, and a mixed solution of hydrochloric acid and aqueous hydrogen peroxide after the step A1.

[20] The method for treating a substrate described in [19], in which the step A1 and the step Ab are alternately repeated.

[21] A method for manufacturing a semiconductor device, including the method for treating a substrate described in any one of [1] to [20].

[22] A kit for treating a substrate, including a chemical solution including ammonium cerium (IV) nitrate and one or more pH adjusters selected from the group consisting of nitric acid, perchloric acid, ammonia, and sulfuric acid, and

one or more rinsing solutions selected from the group consisting of a solution including hydrogen peroxide and an acidic aqueous solution which is other than hydrofluoric acid, nitric acid, an aqueous perchloric acid solution, an aqueous oxalic acid solution, and a mixed aqueous solution of these and does not include hydrogen peroxide.

According to the present invention, it is possible to provide a method for treating a substrate, which can remove transition metal-containing substances on a substrate with high efficiency while inhibiting cerium from remaining on the surface of the treated substrate.

Furthermore, according to the present invention, it is possible to provide a method for manufacturing a semiconductor device including the method for treating a substrate, and a kit for treating a substrate that is applicable to the method for treating a substrate.

