TW200837177A - Chemical mechanical polishing composition - Google Patents

Abstract

The present invention relates to a chemical mechanical polishing (CMP) composition comprising the abrasive grain, acidic component, adjustment agent, and balanced solvent, in which the pH value of the composition is higher than 8 and the concentration of potassium ion is higher than 0.01M. In this composition, potassium-containing base is used as the adjustment agent for modulating the pH value and as the potassium source. On the other hand, by the addition of potassium-containing salt, the concentration of potassium ion is increased so that a higher removal rate can be obtained with low abrasive grain usage when polishing Ta or TaN barrier layer. In addition, the composition is highly selectively to low-K dielectric material and can be used to remove barrier layers quickly.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chemical mechanical polishing composition, and more particularly to a chemical mechanical polishing composition having a high polishing removal rate. [Prior Art] In order to solve the problem that the difference in the surface height of the coating film during the manufacturing process of the integrated circuit leads to difficulty in focusing on the subsequent lithography process, the developed planarization technology plays a key role in the semiconductor industry. With the development of miniaturization of the size characteristics of integrated circuit components, chemical mechanical polishing has become a mainstream and important planarization technology. Chemical mechanical polishing is generally a process in which a semiconductor wafer is placed on a polishing table to planarize the surface of the wafer by applying a polishing ruthenium to a chemical mechanical polishing composition. The mechanism of chemical mechanical polishing is the chemical action of the chemical mechanical polishing composition on the surface of the wafer to change the properties of the surface of the wafer, while using a mechanical grinding method to remove the = (four) plane to achieve the crystal The round surface is smooth and smooth. As a general rule, the entire chemical mechanical grinding process can be roughly divided into two parts, the first is to quickly and massively remove the over-deposited copper part, and then enter the second with a hard barrier layer. In the integrated circuit process is not easy to gas: * Second, the material is the button or nitride button 'but because the button or nitride button + easy to oxidize' is difficult to remove, day P, left basin, , · spear, and ^ Advanced semiconductor micro-morphization of the screen, the barrier layer is more thin and thin, K version of the 匕 p p early layer of the polishing system flattening process to identify those who are difficult. In particular, the chemistry of semiconductor components (4) (4) Calcium into the Ma ^ T chemical mechanical grinding is carried out under the simultaneous contact with the Meng and the barrier layer, and the whole eyebrow is 细 'fine b ▲ compared to the soft and easily oxidized ' or nitrogen The chemical properties of the chemical 1 are harder than that of the stable and firm 19981 5 200837177, so it is important to achieve a good barrier removal effect while maintaining a uniform and smooth copper layer without causing surface defects, which is important in the chemical mechanical polishing process. Question. Therefore, a chemical mechanical polishing composition having a better barrier/metal layer selectivity is particularly important for today's integrated circuit processes. U.S. Patent No. 6,083,840 discloses a chemical mechanical planarization slurry of copper using carboxylic acid as an acidic component. In addition, U.S. Patent No. 5,39, issued to U.S. Patent No. 5-8 discloses an abrasive composition comprising at least two acid radicals, such as tartaric acid, to promote the rate of polishing. U.S. Patent No. 5 discloses a polishing composition containing potassium ferricyanide, potassium acetate, gf acid and a second sol. U.S. Pat. Pub. No. 20070023731 discloses a polishing composition comprising a smear, a potassium persulfate, a potassium persulfate, a potassium peroxylate, an amine oxide, a persulfate, a citric acid, and an iron tartar. None of the above patents reveals the relationship between the concentration of the Group A cation and the removal rate of the barrier layer. Therefore, it is still necessary to quickly remove the chemical mechanical polishing composition of the barrier layer under the conditions of low abrasive content. Φ [Summary of the Invention] The main object of the present invention is to provide a chemical mechanical greening product which achieves high grinding under a low-abrasive element. Another object of the invention is to provide a chemical mechanical polishing composition having good selectivity to pure K. r resistance Γ Γ Month — The purpose is to provide a chemical mechanical polishing composition that can quickly grind and remove the early layer of ρ. For the above and other purposes, the present invention provides a composition comprising abrasive particles, an acid-forming agent, and a solvent for the composition of the composition. The difference is the solvent 19981 6 200837177 * Qin f in the pH value of the composition Above 8, and the concentration of the unloading ions in the composition is 0.01 M or more. The composition is characterized in that the pH of the composition is adjusted by using a test component containing Shu, and the ion source is used as a source for unloading ions. On the other hand, by further adding a salt component containing potassium ions, the composition can be improved. Potassium ion concentration, when the composition is used for grinding or TaN layer, achieves relatively high polishing removal rate under low abrasive particle dosage, and has good selectivity for low-k dielectric materials, especially suitable for use. The barrier layer is removed by rapid grinding. • [Embodiment] The chemical mechanical polishing composition of the present invention includes abrasive grains, an acid forming/knife, a δ week instant agent, and a difference solvent; the composition has a value higher than 8 and a potassium ion concentration of 0.01 M or more. . In the composition of the present invention, generally commercially available abrasive particles can be used, examples of which include, but are not limited to, calcined cerium oxide; unhydrolyzed or hydrolyzed from sodium citrate or lysine, (d) sodium or (4) a sol that is hydrolyzed and condensed by potassium; a sulphur dioxide that is killed or calcined; a cerium oxide that is calcined by sinking; a precipitated or calcined titanium dioxide; or an organic polymer abrasive, or an organic polymer A mixture of materials and inorganic oxide abrasive particles, including composite abrasive particles having different cores: abrasive grains of the outer shell (four) or multiple components. In a preferred embodiment, a cerium sol is used as the abrasive particles. In the composition of the present invention, the abrasive content is not particularly limited, and since the polishing composition of the present invention has a pH value higher than 8 and a potassium ion concentration of 0.01 M? or more, under the condition of low abrasive amount, for example The total weight of the composition is less than 50% of the summer, and the high grinding removal rate can be achieved, especially the high grinding removal rate of 仏 or 19981 7 200837177 * *, thus avoiding the residual or surface of the abrasive particles during chemical mechanical planarization. The disadvantage of scratching. In general, in the composition of the present invention, the abrasive particles are from 01 to 3% by weight based on the total weight of the composition, preferably from 1 to 15% by weight. It is preferred to use an inorganic acid as the acidity of the composition, and examples of the acidic component include, but are not limited to, sulfuric acid, sulfurous acid, phosphoric acid, nitric acid, nitrous acid, hypophosphorous acid, iodic acid, arsenic acid, and methanesulfonic acid. Acid, acetoin, propyl sulphate, benzenesulfonic acid, aminene sulfonic acid, toluene sulfonic acid, hexane sulfonic acid, • decane sulfonic acid, heptane sulfonic acid, 4-amino benzene _3_ Sulfonic acid, bnaphthylamine_4_sulfonic acid, p-toluenesulfonic acid, 6-chloro-3-ylaminoethylbenzene-4-sulfonic acid, 2-propylene/sulfonic acid, 2-propene-1- Sulfonic acid, 4-nitrosophthalene-2-sulfonic acid, alkylbenzenesulfonic acid, dodecyl benzoic acid, toluene acid, citric acid, read, or stearic acid. By adjusting the type and content of the acidic component, the desired removal rate of the copper layer can be obtained. Generally, §, the acidic component is from 〇5 to 重量%, preferably from 0.1 to 5% by weight, more preferably from 5 to 3% by weight, based on the total weight of the composition. #产" In the composition of the present invention, an alkaline component containing potassium, such as potassium hydroxide, is used as a regulator to adjust the pH value of the composition, and other tests for adjusting ρΗ may be used alone or in combination. Sexual components, such as tetramethylammonium oxide. Usually, the pH adjusting agent is 〇〇5 to $% by weight based on the total weight of the composition, preferably 〇1 to i% by weight based on the total weight of the product, and is only sufficient to make the 誃 composition PH 胄 8 or more. The pH of the composition is preferably in the range of 9 to 9. Containing the alkaline component of the unloading, in addition to adjusting the pH value of the composition, and also acting as a dismounting ion in the composition to enhance the barrier layer of the barrier layer, such as the W or Niobium (10) barrier, 19981 8 200837177 研磨 φ grinding removal rate. In one embodiment, the potassium ion concentration in the composition of the present invention is 0.01 Å or more, preferably 0.15 to 0.5 Å, and more preferably 0. 2 to 0.3 Å. On the other hand, in the composition of the present invention, a salt component containing potassium ions may be added as an accelerator as needed to further increase the potassium ion concentration in the composition. Examples of the salt component containing potassium ions include, but are not limited to, potassium carbonate, potassium citrate, potassium sulfate, cesium potassium phosphate, potassium oxalate, potassium potassium triacetate pentaacetate, or potassium hydrogencarbonate. Other additives such as hydrogen peroxide may also be included in the composition of the present invention to increase the polishing removal rate of the barrier layer or to improve the properties of the abrasive composition. The difference between the compositions is a solvent, and in one embodiment, water is used as a solvent, and deionized water is preferably used as a solvent for the abrasive composition. The features and effects of the present invention are further illustrated by the following specific examples, but are not intended to limit the scope of the invention. Example 0 The grinding test of each of the following examples was carried out according to the following conditions: Applied Materials Mirra Polisher Polishing pad: Rodel IC1010 Membrane pressure: 2 psi Turntable speed: 90 rpm Grinding head speed: 84 rpm Inner tube (Intertube) · 3 psi Retaining ring: 3 psi Slurry flow rate: 200 ml/min 9 19981 200837177 * * Example 1 According to Table 1, the use includes acid, two gasification; ε 夕 (average particle size of about 80 Grinding test of six different compositions of grinding composition such as rnn's Colloidal silica, tetraammonium hydroxide adjusting agent, and potassium ion-containing accelerator, and copper (Cu) layer, tantalum (Ta) The removal rates of barrier layers and different materials such as Tetraethylortho Silicate (TEOS) dielectric layers are reported in Table 2. La lb lc

Id le

If L50 3.00 3·00 Table Citric Acid (wl% A burnt acid (wt%)

The result of the reduction of Table 2 does not increase the concentration of hydrogen and oxygen in the milled component. The concentration of potassium hydroxide helps to increase the removal rate of the Ta layer. By changing the amount of acid used, it is possible to allow the use of different amounts of unloading ions in the interval of adjustment to an appropriate pH value, thus causing the desired removal effect, and (iv) removing the barrier. 3 19981 10 200837177 λ Reference Example 2 According to Table 3, six light including acid, cerium oxide (colloidal silica with an average granules of about 80 nm), a regulator, and different ionizing sources were used. The grinding composition sample (2a-2f) is subjected to a grinding test with respect to the sample (2) without the addition of the ion source, and the copper (Cu) layer, the button (Ta) barrier layer, and the gasification button (TaN) barrier layer are subjected to a grinding test. The removal rates of different materials such as BD and TEOS dielectric layers and the potassium ion content of the polished composition samples are shown in Table 4.

19981 11 200837177 According to the results in Table 4, the potassium ion source in the grinding composition sample can increase the potassium ion concentration in the sample and increase the removal rate of the Ta barrier layer compared to the control sample. The potassium ion concentration in the sample and the removal rate of the copper layer, the button barrier layer, and the nitride button barrier layer are shown in Figures la, lb, and 1c. Example 3 According to Table 5, a grinding composition sample comprising a different acid, cerium oxide (Colloidal silica having an average particle diameter of about 80 nm), a hydroxide modulating agent, *, and a potassium carbonate accelerator was used. A grinding test was performed, and removal rates of different materials such as a copper (Cu) layer, a tantalum (Ta) barrier layer, a tantalum nitride (TaN) barrier layer, and a Tetraethylortho Silicate (TEOS) dielectric layer were performed. Recorded in Table 6. Table 5 Barium peroxide (wt%) sulfuric acid (wt%) phosphoric acid (wt%) citric acid (wt%) cerium oxide (wt%) potassium carbonate (wt%) potassium hydroxide (wt%) 3a 5.00 - - 0.61 5.00 2.23 0·6 3b LOO - - 0.61 5.00 2.23 0.6 3c 5.00 - 0.61 - 5.00 2.23 0.6 3d 5.00 0.61 - 5.00 2.23 0.6 Table 6

Cu (A/min) Ta (A/min) TaN (A/min) TEOS (A/min) 3a 570 541 815 359 3b 440 435 660 489 3c 592 545 793 415 3d 1100 535 783 421 According to the results of Table 6, Increasing the concentration of hydrogen peroxide in the sample of the abrasive composition helps to increase the removal rate of the Ta layer, while the acidity contributes to the removal rate of the Cu layer by 12 19981 200837177 * *. Example 4 According to Table 7, the grinding composition samples (4a-4j) including the acid, the cerium oxide (colloidal silica having an average particle diameter of about 80 nm), a regulator, and an accelerator were used together with the control sample. (4) Performing a grinding test, and a copper (Cu) layer, a group (Ta) barrier layer, a nitrided layer (TaN) barrier layer, a carbon doped oxide (CDO), and a tetraethoxyl group The removal rates of different materials such as TEOS dielectric layers are reported in Table 8.

19981 200837177 Table 8

Cu (A/min) Ta (A/min) TaN (A/min) CDO (A/min) TEOS (A/min) 4a 100 418 614 598 182 4b 3 66 481 697 563 223 4c 145 464 675 751 299 4d 421 441 634 663 266 4e 103 230 330 294 88 4f 110 307 43 8 393 156 4g 243 267 419 395 186 4h 283 463 722 750 361 4i 675 480 758 493 243 4j 2067 485 747 296 301 4 66 232 356 444 165

According to the results of Table 8, the addition of potassium hydroxide can increase the removal rate of the tantalum (Ta) barrier layer, and if combined with potassium carbonate, the removal rate of the barrier layer (Ta) can be further improved. However, the above-described embodiments are merely illustrative of the principles of the present invention and its effects, and are not intended to limit the present invention, and those skilled in the art can practice the above embodiments without departing from the spirit and scope of the present invention. Make modifications and changes. Therefore, the scope of protection of the present invention should be as set forth in the scope of the claims described later. [Simple diagram of the diagram] The first diagram shows the potassium ion concentration and the removal rate of the copper layer; the lb diagram shows the potassium ion concentration and the removal rate of the barrier layer; and the lc diagram shows the potassium ion concentration and nitridation. The removal rate of the barrier layer. 14 19981

Claims (1)

200837177 X. Patent application scope: 1 · A chemical mechanical polishing composition comprising: (A) abrasive particles; (B) an acidic component; (C) a regulator; and an upper (D)|a solvent; wherein the composition The value of the substance is higher than 8 and the potassium ion concentration in the 5 liter composition is 0.01 M or more. Such as the declaration of the patent dry circumference! The composition of the item, wherein the composition has a pH of from 9 to 丨3. The potassium ion concentration of the composition of claim 1 is 〇15 to 0.5M. For example, the potassium ion concentration of the composition of the scope of the patent application is 〇·2 to 〇.3Μ. Such as the scope of patent application! The composition of the item - a ... ~ ^ calcined cerium oxide; cerium sol formed by hydrolysis of sodium citrate or potassium citrate or hydrolysis of decane, hydrolysis or condensation of sodium citrate or potassium citrate; 2 precipitation or calcination The third oxidation of the third; the diurnal or calcined dioxins; the sink or calcined titanium dioxide; or the organic polymer abrasive particles, or the organic high-fraction f material and the inorganic oxide abrasive mixture, including different cores A group consisting of abrasive grains of a casing material or composite abrasive grains of a plurality of components, the composition of the first aspect of the patent, wherein the abrasive sol. , the scope of patent application! The composition of the item, wherein the abrasive grains account for, and the total weight of the product is (U to 30%. 2. 3. 4. 5. wherein, in the composition, among the composition, the mill The granules are selected as the composition of the first aspect of the patent application, wherein the acidic component is a mineral acid. 9. The composition of claim 1, wherein the acidic component It is selected from the group consisting of sulfuric acid, sulfurous acid, phosphoric acid, nitric acid, nitrous acid, hypophosphorous acid, acid-breaking, sulphuric acid, phthalic acid, ethyl citrate, propeatin, benzoic acid, aminene benzene sulfonic acid, toluene Sulfonic acid, hexanesulfonic acid, decanesulfonic acid, heptanesulfonic acid, 4-aminotoluene-3_sulfonic acid, naphthylaminesulfonic acid, p-toluenesulfonic acid, 6-murine-3-aminoethyl Benzene-4-hemeic acid, 2-propylene-1-hemeic acid, 2-propionyl-1 _® sulfonic acid, 4-nitroguanidine-2-sulfonic acid, alkylbenzene sulfonic acid, twelve a group consisting of benzenesulfonic acid, toluenesulfonic acid, citric acid, selenic acid, and selenous acid. 10. The composition of claim 1, wherein the acidic component accounts for the total weight of the composition. 0.05 to 1 〇%. U. The composition of claim 1, wherein the regulator comprises an organic component of potassium. _12. The composition of claim n, wherein the regulator accounts for the total composition.重 至 至 〇 至 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 组成 组成 组成 组成 组成 组成 组成 组成 组成 组成 组成 组成 组成 组成 组成 组成 组成 组成 组成 14 14 14 14 14 14 14 14 14 14 14 The salt component containing potassium ions is selected from the group consisting of potassium carbonate, potassium citrate, sulphate, potassium hydrogen hydride, potassium oxalate, potassium salt of diethyltriamine pentaacetate, and potassium hydrogencarbonate. The composition of claim 1, wherein the solvent is water. 16 19981