TWI227271B - Post chemical mechanical polishing (CMP) cleaning solution - Google Patents

Abstract

A post-CMP cleaning solution is used for removing the contaminant adhered on wafer surfaces, and the post-CMP cleaning solution includes an amine derivative, an organic carboxylic acid, an inhibitor, and a surfactant. The amine derivative removes particles from the wafer easily. The organic carboxylic acid chelates with metal ion to reduce their contamination. The inhibitor forms a passivation layer on Cu surface to prevent Cu further oxidation. The surfactant increases the wettability of the wafer surface to enhance particles removal efficiency.

Description

1227271 V. Description of the invention α) Field of the invention The present invention relates to a planarization process in a integrated circuit manufacturing process, and in particular to a cleaning solution after chemical mechanical polishing (Chemical Mechanism Po 1 sh i ng 5 CMP). BACKGROUND OF THE INVENTION In the Very Large Scale Integration (VLSI) and Ultra-Large Scale Integration (ULSI) semiconductor wafers, the connection of various components is mainly by wires, and the wires and the integrated circuits The connection part of the component is generally called a contact window, and the connection between the wire and the wire is called a via window. The resistance of the wire itself and the size of the parasitic capacitance between the wires are one of the decisive keys affecting the speed of the component. Therefore, after the semiconductor process enters the deep sub-micron field, copper is used instead of aluminum to make interconnects. In conjunction with low-k materials, the inter-metal dielectric layers (Inter-Metal Dielectrics (iMD)) are effective Reduce the resistance and delay effect (RC Delay) and improve the ability to resist electromigrating. This is because the electromigration resistance of copper is 30 to 100 times that of aluminum, the resistance of the interlayer window is reduced by 10 to 20 times, and the resistance is reduced by 30%. Moreover, it is very difficult to etch copper #, so the-= inlaying process instead of the traditional wire is directly defined

Copper metal interconnects. + 衣 W In the metal inlaying process, the lack of process technology is a mechanical grinding process of crystal car with an appropriate chemical additive. It is an indispensable use of mechanical grinding, and the surface of the circle is undulating. Sharpen the outline

⑵ 1227271 V. Description of the invention Flat technology. The chemical used in the general chemical mechanical grinding process is generally referred to as slurry, where the slurry is usually composed of metal abrasive particles (such as alumina (A 1 um) na), organic acids, and surfactants. Mixed with oxidants (such as iron nitrate, potassium iodate, etc.). '' However, the chemical mechanical polishing process is very easy to cause wafer surface staining, that is, particles and metal ions on the surface of the wafer that are not easily removed after chemical mechanical polishing. In addition, it comes from the wafer itself. If > contamination and metal ion contamination remain on the wafer surface, the yield and guilt will be reduced. Therefore, in order to remove the pollutants produced by chemical mechanical polishing, a clear solution must be added after the chemical mechanical polishing process. Β 目 β 'Industry uses brushing, spraying, and ultrasonic cleaning to dilute ammonia, and the solution is used to clean the surface of the wafer to To achieve the effect of removing the wafer surface. The principle of ammonia particle removal is that the surface of the wafer is slightly charged so that the particles and the wafer surface have the same charge and repel each other. Grinding, particles and metal ions will remain on the hydrophobic surface of the wafer and be removed by the cyanide aqueous solution, which will lead to a reduction in product yield. In addition, in the chemical mechanical polishing process, the copper oxide in the slurry is reacted to form a layer of copper oxide, cuprous oxide and copper hydroxide on the surface of the copper metal layer). This copper oxide layer not only contaminates particles and metal ions, but also has a resistance value that affects the electrical properties of the device and may cause leakage or problems at the interface of the wire. Summary of the invention 1 学 助剂 Oxide # Proper surface fouling leaving a lot of ionic fouling particle-causing components after the process of production and washing steps, the name of the fouling substance, and due to the difficulty of research, the agent will interact with the substance (oxygen: easy to attach high and will deteriorate) Wait

1227271

V. Description of the invention (3) In view of this, one object of the present invention is to provide a cleaning solution after chemical mechanical polishing, which can not only effectively remove particulate contamination and metal ions remaining on the wafer surface after chemical mechanical polishing. It can remove the metal oxide layer on the surface of the metal layer, reduce the resistance value of the metal layer (wire), improve the electrical properties of the device, and avoid problems such as leakage or degradation of the interface of the metal wire. The invention provides a cleaning solution after chemical mechanical polishing, which is used to remove at least one pollutant attached to the wafer surface. The cleaning solution after chemical mechanical polishing is at least composed of an amine derivative, an organic Organic acid (Organic Carboxylic Acid), an inhibitor (Inhibitor) and a surfactant (Surf actant). Among them, the amine derivative can remove the wafer surface, so that the particles and the wafer surface have the same charge and repel each other, so the particles can be easily removed from the wafer. Organic carboxylic acid groups can react with metal ions to form stable metal chelates, so they can effectively remove contaminating metal ions. The inhibitor can react with the metal layer to form a passivation layer to prevent oxidative corrosion on the surface of the metal layer. Interface activator; make Wan: the surface of the film mechanically polished from hydrophobic to hydrophilic in order to increase: surface wettability, so that the cleaning solution to remove particles is greatly improved ^. In addition, the cleaning solution of the present invention does not cause defects formed by chemical mechanical grinding: such as a copper metal layer or a dielectric layer, and can reduce the metal. The resistance value decreases, and the yield loss of the product is reduced. " Amine derivatives are, for example, tetramethylamnioniuni hydroxide (TMAΗ), n-amylamine, tetraethylammonium hydroxide (T tylamine ^ vietraethylaramonium

1227271 V. Description of the invention (4) hydroxide, TEAH), etc. Organic carboxylic acids such as maleic acid, L-ascorbic acid, acetic acid, and oxalic Acid), Citric Acid, Tartaric acid, Malic acid, Malonic acid, etc. Inhibitors are, for example, benzotria (β enz 〇triaz 〇1 e) and its derivatives' surfactants are commonly used surfactants in the general industry, including cationic, anionic or nonionic surfactants . In addition, the cleaning solution after the chemical mechanical grinding of the present invention includes a mixed solution of hydroxide = tetra-ammonium / benzotriazole / citric acid. Among them, the acid-base value (ρΗ value) of the tetramethylene hydroxide / benzylpyridine / citric acid mixed solution can be 2 to the acid of the tetramethylsulfonate / benzylpyridine / citric acid mixed solution of rat gasification. Test value pH value) The car is preferably 2.5 to 5.5. The pH value of the tetramethyl beryllium hydroxide / benzotriazole mixed solution is more preferably 3 to 4.5. Ding Xixi The present invention further provides a method of chemical conversion including providing a tool and then at least including mechanical mechanics and chemical mechanical grinding through chemical mechanical research. The present invention is to remove particles with the same charge on the surface; The copper metal layer reacts with an amine derivative and then cleans the amine-soluble derivative to mutually reciprocate the acid and remove gold from the solution. After the grinding, the organic carboxy bottom is rounded and can react with the shaped metal to prevent the cleaning of copper. The metal layer is washed with acid and one by one to make it easy to form stable ions. The metal layer method, the substrate, and the inhibitor process. Particles and wafers from metal chelates on the wafers with inhibitor surface oxidation

9482twf.ptd Page 9 1227271 V. Description of the invention (5) Wetness of the surface after mechanical grinding, mechanically grinding materials, reducing metal conductivity can improve products and advantages can be more drawings, for corrosion. In addition, in the cleaning solution of the present invention, the boundary is added: in the J method, the cleaning solution can remove particles from the cleaning agent to increase the wafer surface. Moreover, the clearing of the invention is greatly improved. Materials (such as copper metal layers or dielectric fluids) will not cause the resistance value of the chemical mechanical wire (that is, S can be raised) to be defective, and the yield can be improved. ), And it is clearly easy to understand, the following is a special purpose ^ ^ other purposes, features, and detailed description are as follows: Another example, and with the reference numerals of the drawings to explain 100 substrate 102 dielectric layer 104 opening 106 barrier layer 108 metal Layer 110 Grinding slurry 112 Copper ions The chemical solution of the present invention # ^ 例 例 生物 、 生物 # The cleaning solution after mechanical milling includes at least amine derivatives, inhibitors and amines, ascorbic acid, Ethylmalonate, etc. The agent is a general industry amine derivative such as ag tetra 7 phosphonium succinate / hydrazine emulsified tetraphosphonium ammonium, n-pentyl tetraethylbismuth. The organic carboxylic acids are, for example, maleic acid, oxalic acid, citric acid, dihydroxybutane: a & \ 歹 工 Ί ~ acid, pico acid, inhibitors such as benzotriazole and its derivatives. Interfacial activity

1227271 V. Description of the Invention (β) The interface activity used in the boundary suspension is dense || 6 Fu Xing * ^ Contains cationic, anionic scraping, and interfacial surfactants. The t or non-ionizable amine derivatives can dissolve the wafer 矣, ./ib/ t with the same charge and repel each other, because the phase on the wafer surface is removed. Organic acid acid can be chelated (Metal-Che late), so it can be right to metal ion from 乂 %% 疋. Inhibitors can be counter-stored with the metal layer :: ^^> Dyeable gold, gasification and corrosion residue. Surfactants can greatly improve the particle removal ability of menses. … And the use concentration of the chemical-mechanical abrasives disclosed in the present invention is described as follows: The concentration of each amine-forming derivative in the valley liquid is about 0.05% to 0.05%. The concentration of the organic carboxylic acid is about 0.01% to 0.05%. The concentration of the inhibitor was from 0.1% to 0.2% / right. The concentration of the surfactant is about 0.005% to 0 °. ^%. In the following embodiments of the invention, the cleaning solution after chemical mechanical grinding is tetramethylammonium oxide (TMAΗ) of Uticola spp., Stem: CCA) ^ ^ ^ ^ ^-Benzodiazole (BTA), citric acid Example to explain. Among them, tetramethylammonium hydroxide / benzene I Yada, the acid test value (pH value) of the mixed acid solution can be 2 to 11. Hydroxide A 2 The tetrabasic benzodiazole / citric acid mixed solution has a better pH (pH value) ΐ 乂 Λ. The pH value of the mixed solution of tetramethylammonium oxide, benzotriazole, and citric acid is preferably 3 to 45. In order to explain the present invention in more detail, experimental examples of the present invention are given below.

1227271 V. Description of the Invention (7) to 4 and Comparative Examples 1 to 4 to evaluate the cleaning solution after chemical mechanical polishing on copper metal layer / silicon oxide (TEOS) thickness, wafer defect number, copper ion concentration and electrical properties influences. Comparative example 1 (solution A): tetramethylamine hydroxide aqueous solution (TMHA = 25%) Comparative example 2 (solution B): tetramethylamine hydroxide and benzotriazole aqueous solution (TMAH / BTA: 0.4% / 0.05%) Comparative Example 3 (Solution C): Aqueous solution of tetramethylamine hydroxide and citric acid (TMAH / Citric acid = 0.4% / 0.1%) Comparative Example 4 (Solution D): Aqueous solution of citric acid (Citric acid = 0, 1% /) Experimental example 1 (E solution) ·· Tetrafluorenyl hydroxide, benzotriazole and lemon

Aqueous solution of acid (TMAH / BTA / Citric acid = 0.4% / 0.05% / (K 0 2 0 / 〇), pH value = 10) Test Example 2 (F solution): tetramethylamine hydroxide, Aqueous solution of saccharine and clavulanic acid (TMAH / BTA / Citric acid = 0.4% / 0.05% / q1%), pH value = 5.5. Experimental example 3 (G solution): tetramethyl hydroxide Aqueous solution of succinylamine, benzotriazole and quinine-like acid (TMAH / BTA / Citric acid = 0.4% / 0.05% / 〇2%), pH value = 4 Experimental Example 4 (fluorene solution): hydroxide Aqueous solution of tetramethylamine, benzotriazole and citric acid (TMAH / BTA / Citric acid = 0.4% / 0.05% / 〇2%), pH = 3.8 ~ 4.2, surfactant = 0.05% Manufacturing process according to the metal mosaic structure shown in Figures 1A to 1B +

1227271 V. Description of the invention (8) step, making a plurality of test samples. Then, wash the test samples (solutions A to H) after chemical mechanical polishing with experimental examples 丨 to 4 and comparative examples 1 to 4, respectively. First, please refer to Figure 1A to provide a substrate 丨 〇〇 A dielectric layer 10 is formed on the substrate \ 00, and the material of the dielectric layer 102 is ^ if it is tetra-ethyl-o-silicate (Tetra Ethyl 〇rth.

Si 1 1 cate ’TEOS) / ozone (〇3) is silicon dioxide formed by a reactive gas source using chemical vapor deposition. After that, a portion of the dielectric layer 〇 2 is removed to form an opening 104 having a size of about 0.15 // ra (aspect ratio 1: j to 1 〇 · 1) in the dielectric layer 102. Then, a conformal barrier layer 106 is formed on the substrate 100. The material of the barrier layer 106 is, for example, titanium nitride. Thereafter, a metal layer 108 is formed on the substrate 100 to fill the openings 104. The metal layer 108 is, for example, copper metal. Please refer to Figure 1B for the chemical mechanical polishing process. First, grind the steel and grind the slurry to remove the openings. 丨 Part of the metal layer other than 0 丨 0 8 until the storm barrier layer 1 〇 β ', and then grind. The slurry of the dielectric layer 〇04 removes part of the metal layer 008 except the opening 〇0 until the surface of the dielectric layer 〇2 is exposed. A chemical machine is performed; after the mechanical grinding process, the surface of the metal layer is oxidized to oxide, cuprous oxide, or copper hydroxide, and many mortar particles 11 are attached to the surface of the metal layer 108, and the wafer Many metal ions 11 2 are attached to the surface of the (dielectric layer 1 0 2). Said. After the test sample is prepared, first spray the surface of the test sample (wafer) with deionized water, and then use the cleaning solutions (eight solutions to Η) after chemical mechanical polishing of Experimental Examples 1 to 4 and Comparative Examples 1 to 4, respectively. Solution) sprayed onto the test sample

1227271 V. Description of the invention (9) (Yueyuan), and brush on both sides with a brush. "After spray-washing the surface of the test sample (wafer), pick up the sample with deionized water (wafer). After drying the test sample in a rotating manner, the test sample _ thickness loss test, defect test, respectively ::: (Copper) / dielectric ^ Analysis.% ION test and electrical metal layer (steel) / dielectric layer (TE0S) thickness loss. After the test sample is ground, #front to KLA Tencor film / Huhoudan And the sound layer of the dielectric layer of the cleaning process has not been cleaned, the metal layer on the test sample is clear: ϊίί. After the test sample has been subjected to chemical mechanical polishing & α, without clothes The thickness of the metal layer and the dielectric layer is described by the KLA Tencor film. The thickness of the metal layer and the dielectric layer before the cleaning process on the test sample of the metal reed are all sound. JJ Ϊ is the thickness after chemical mechanical polishing after cleaning, the difference between the two is the monthly loss. The dielectric layer is cleaned after chemical mechanical polishing ^, '5 == and the dielectric layer is subjected to chemical Thickness of 2 ^% after mechanical grinding a soil > vww & After the manufacturing process, the difference between the two is the thickness of the dielectric layer (TE0s). Defect test 'Dry ί iH sample τ Clean process after chemical mechanical polishing and m, 4 Ku Tencor defect scan The instrument scans the test sample (crystal) to measure the number of defects on the test sample (wafer). Copper ion concentration test and electrical analysis Dry the test sample after the chemical mechanical polishing cleaning process and know, Total reflection X-ray fluorescence (T〇tal Reflection 9482twf.ptd Page 14 1227271 V. Description of the invention (10) X-ray Fluorescence (TXRF) Measure the metal ion concentration on the test sample (wafer) and The resistance value (electrical analysis) of the metal layer on the test sample (wafer). Next, the effect of the present invention will be explained. The second figure shows the results after chemical mechanical polishing of Experimental Examples 1 to 4 and Comparative Examples 1 to 4. Schematic diagram of the thickness loss of the metal layer (copper) / dielectric layer (TE0S) of the wafer processed by the cleaning solution. As shown in FIG. 2, the thickness of the dielectric layer (TE0S) of Experimental Examples 1 to 4 and Comparative Examples 1 to 4 The losses are less than 20 Angstroms, and the gold of Experimental Examples 1 to 4 The layer (copper) thickness loss is less than the metal layer (copper) thickness loss of Comparative Examples 1 to 4. Furthermore, the cleaning solutions (a solution to rhenium solution) after chemical mechanical polishing of Experimental Examples 1 to 4 and Comparative Examples 1 to 4 ), The cleaning solution added with benzotriazole, the thickness of the metal layer (copper) was lost, and the addition of benzodisal was smaller. Figure 3 shows the experimental examples 1 to 4 and Schematic diagram of the number of defects of wafers treated with cleaning solution after chemical mechanical polishing of Comparative Examples 1 to 4. As shown in FIG. 3, the number of defects of Experimental Examples 1 to 4 is less than that of Comparative Examples 1 to 4. Therefore, the cleaning solution after chemical mechanical polishing of the present invention can effectively remove the contaminated particles on the wafer and reduce defects on the wafer. Moreover, in the cleaning solutions (A solution to rhenium solution) after chemical mechanical polishing of Experimental Examples 1 to 4 and Comparative Examples 1 to 4, the cleaning solution with benzotriazole was added, and the number of defects on the wafer was less than that without addition. Benzotriazole is better. Fig. 4 is a graph showing the relationship between the copper ion concentration of wafers treated with the cleaning solutions after chemical mechanical polishing of Experimental Examples 1 to 4 and Comparative Examples 1 to 4. As shown in FIG. 4, in Experimental Examples 1 to 4, the copper ion concentration on the wafer surface decreases as the pH value of the cleaning solution decreases. Therefore, the chemistry of the present invention

9482twf.ptd Page 15 1227271

5. Description of the invention (11) In the cleaning solution after mechanical grinding, the pH value of the mixed solution of tetramethylammonium hydroxide / benzotriazole / citric acid can be 2 to 11. The pH (pH value) of the mixed solution of tetramethine hydroxide / benzotriazole / citric acid is preferably 2.5 to 5.5. The pH value of the tetramethylammonium hydroxide / benzotriazole / citric acid mixed solution is preferably 3 to 4.5. In addition, in the cleaning solutions after the chemical mechanical polishing of Experimental Examples i to 4 and Comparative Examples i to 4 (solution A to rhenium solution), the cleaning solution with citric acid added had the effect of removing metal ions less than without citric acid added. Those who are better. . Figure 5 shows the chemical machines using Experimental Examples 1 to 4 and Comparative Examples 丨 to 4.

The electrical properties of the wafer after mechanical grinding of the cleaning solution (A solution to rhenium solution) are shown in the figure. As shown in FIG. 5, the resistance values of the metal layers measured in Experimental Examples 1 to 4 and Comparative Example 2 were about 0.080 ohm to 0.885 ohm. Wherein, the resistance value of the metal layer measured in the cases 1, 3, and 4 is greater than 8500 ohms, and the chemical mechanical polishing and washing solutions i of Experimental Examples 1 to 4 and Comparative Examples 1 to 4 The cleaning solution with benzotrisial is added to the machine on the wafer; ^ The resistance value is lower than those without benzotrisal. Because of & the addition of benzotri-4 to the chemical ΪΪΓί washing solution is helpful to slow down the increase in the resistance of the wire.

Movement hair: After the f mechanical chemical grinding process, the amine derivatives, ir, amine: made! : Washing process of mixed solution of surfactant. Refers to the same table, “Making the particles on the surface of the wafer”, so the particles can be easily separated from the wafer. The enemy group can react with metal ions to form a stable metal sound. . Uetal-chelate), so it can effectively remove pollution

1227271 V. Description of the invention (12) Metal ions. Inhibitor (benzotriazole), a copper-benzotriazole passivation layer to prevent the formation of gaseous layer reaction of the copper metal layer. Surfactants can be chemically and mechanically ground thin, surface oxidation corrosion. Water solubility to increase the wettability of the wafer surface, and: = changed from hydrophobicity to affinity. / Bow wash liquid to remove particles In the embodiment of the present invention is copper metal-the chemical machine of the present invention; rt speaks β, belongs to the general example, of course, copper alloys, such as copper aluminum alloy can also be applied The metal-containing dielectric layer is not limited to oxidation, and, in the embodiment of the present invention, or the low-dielectric material i may be lin ..., a glass although the date and month P of the present issue, to limit the & sundial The preferred embodiment is disclosed as above, but it does not use God and Yu pq in January. "Any person skilled in this art" makes various changes and retouches in Tian who does not depart from the scope of the present invention. The appended application patents shall prevail.

Ptd 9482twf, Page 17 1227271 Brief Description of Drawings Figures 1A to 1B are flowcharts showing the manufacturing process of a metal mosaic structure according to a preferred embodiment of the present invention. Figure 2 is a schematic diagram showing the thickness loss of a metal layer (copper) / dielectric layer (TEOS) of a wafer treated with chemical mechanical polishing polishing solutions of Experimental Examples 1 to 4 and Comparative Examples 1 to 4. FIG. 3 is a schematic diagram showing the number of defects of wafers treated with the chemical mechanical polishing polishing solutions of Experimental Examples 1 to 4 and Comparative Examples 1 to 4. FIG. Fig. 4 is a schematic diagram showing the copper ion concentration of the wafer treated with the chemical-mechanical polishing solutions of Experimental Examples 1 to 4 and Comparative Examples 1 to 4. FIG. 5 is a schematic diagram showing the electrical properties of the wafers treated with the chemical mechanical polishing polishing solutions of Experimental Examples 1 to 4 and Comparative Examples 1 to 4. FIG.

9482twf.ptd Page 18

Claims (1)

1227271 VI. Application Patent Scope 1. A cleaning solution after chemical mechanical polishing, which is used to remove at least one pollutant attached to the wafer surface. The cleaning solution after chemical mechanical polishing includes at least: an amine derivative; An organic carboxylic acid; and an inhibitor. 2. The cleaning solution after chemical mechanical grinding as described in item 1 of the scope of the patent application, wherein the amine derivative is selected from the group consisting of tetramethylammonium hydroxide, n-pentylamine and tetraethylammonium hydroxide. 3. The cleaning solution after chemical mechanical grinding as described in item 1 of the scope of the patent application, wherein the organic pelic acid is selected from the group consisting of maleic acid, L-ascorbic acid, acetic acid, oxalic acid, citric acid, malic acid , Malonic acid and dihydroxysuccinic acid group. 4. The cleaning solution after chemical mechanical grinding as described in item 1 of the scope of the patent application, wherein the inhibitor is selected from the group consisting of benzotrisial (B e η ζ 〇tria ζ ο 1 e) and derivatives thereof. Ethnic group. 5. The cleaning solution after chemical mechanical grinding as described in item 1 of the patent application scope, which further includes a surfactant. 6. The cleaning solution after chemical mechanical grinding as described in item 1 of the scope of patent application, wherein the cleaning solution after chemical mechanical grinding comprises a mixed solution of tetramethylammonium hydroxide / benzotriazole / citric acid. 7. The cleaning solution after chemical mechanical grinding as described in item 1 of the scope of patent application, wherein the acidity test value (pH value) of the mixed solution of tetraammonium hydroxide / benzotriazole / citric acid includes 2 to 11 . 9482twf.ptd Page 19, 1227271 6. Application for Patent Scope 8 · The cleaning solution after chemical mechanical grinding as described in item 1 of the scope of patent application, where the mixed solution of tetraammonium hydroxide / benzotriazole / citrate The pH value (pH) includes 2.5 to 5.5. 9 · The cleaning solution after chemical mechanical grinding as described in item 1 of the scope of patent application, wherein the pH value of the mixed solution of the tetramethylammonium hydroxide / benzotriazole / citric acid includes 3 to 4.5 . 1 0 · A cleaning method after chemical mechanical grinding, the method includes the following steps: providing a substrate having a metal layer after chemical mechanical grinding; and including at least an amine derivative and an organic carboxylic acid The substrate is subjected to a cleaning process with a cleaning solution after chemical mechanical polishing with an inhibitor. 1 1 · The cleaning method after chemical-mechanical grinding as described in item 丨 0 of the scope of patent application, wherein the amine derivative is selected from the group consisting of tetramethylammonium hydroxide, n-pentylamine and rat emulsion Ethnic group. 1 2 · The cleaning method after chemical mechanical grinding as described in the item No. of the application scope, wherein the organic acetic acid is selected from the group consisting of maleic acid, L-ascorbic acid, acetic acid, oxalic acid, citric acid, apple Acid, malonic acid and dihydroxysuccinate. 1 3. The cleaning method after chemical mechanical grinding as described in item 10 of the scope of patent application, wherein the inhibitor is selected from the group consisting of Benzotriazole and its derivatives. 1 4 · After chemical mechanical grinding as described in item 10 of the scope of patent application 9482twf.ptd Page 20 1227271 6. Scope of patent application The cleaning method, wherein the cleaning solution after chemical mechanical grinding further includes a surfactant. 15 β The cleaning method after chemical mechanical grinding as described in item 10 of the scope of the patent application, wherein the cleaning solution after chemical mechanical grinding comprises a mixed solution of tetraammonium hydroxide / benzotriazole / citric acid. 16. The cleaning method after chemical mechanical grinding as described in item 15 of the scope of patent application, wherein the acid test value (ρ Η value) of the mixed solution of tetramethylammonium hydroxide / benzotriazole / citric acid Including 2 to 11. 1 7. The cleaning method after chemical mechanical grinding as described in item 15 of the scope of patent application, wherein the acid test value (pH value) of the mixed solution of tetramethylammonium hydroxide / benzotriazole / citric acid includes 2 5 to 5.5. 1 8. The cleaning method after chemical mechanical grinding as described in item 15 of the scope of patent application, wherein the acid test value (pH value) of the mixed solution of tetramethylammonium hydroxide / benzotriazole / citric acid includes 3 to 4.5. 9482twf.ptd Page 21