KR102261822B1 - Cmp slurry composition with reduced defect occurrence and preparation method thereof - Google Patents

Abstract

According to the embodiment, by controlling the content of polyvalent metal ions together with the total content of metal ions in the composition, and controlling the ratio of the polishing rate to the silicon oxide film and the copper film to a certain range, while securing the target polishing performance, defects It is possible to provide a slurry composition capable of reducing the occurrence of Accordingly, the slurry composition may be applied to a semiconductor device manufacturing process including CMP to improve the quality of products including semiconductor substrates.

Description

CMP slurry composition with reduced defect occurrence and method for manufacturing the same {CMP SLURRY COMPOSITION WITH REDUCED DEFECT OCCURRENCE AND PREPARATION METHOD THEREOF}

Embodiments relate to slurry compositions used in chemical mechanical polishing (CMP) processes. More specifically, the embodiment relates to a CMP slurry composition capable of reducing the occurrence of defects while ensuring polishing performance, a method of manufacturing the same, and a method of manufacturing a semiconductor device using the same.

As the semiconductor device becomes more precise and dense, a finer pattern forming technique is used, and accordingly, the surface structure of the semiconductor device becomes more complicated and the step difference between the interlayer films is also increasing. In manufacturing a semiconductor device, a chemical mechanical polishing (CMP) process is used as a planarization technique for removing a step difference between layers formed on a semiconductor substrate such as a wafer.

In the CMP process, in a state where the semiconductor substrate on which the film is formed is attached to the head and brought into contact with the surface of the polishing pad formed on the platen, a slurry composition is supplied to chemically react the surface of the semiconductor substrate to the platen and the head. It is to mechanically planarize the uneven portion of the surface of the semiconductor substrate by relative motion.

As such, the raw material of the slurry composition essentially used in the CMP process is largely composed of abrasive particles that perform physical polishing and additives that perform chemical polishing or protection. _{For example, in the case of silica (SiO 2} ) of abrasive particles performing physical polishing, a slurry composition dispersed in a colloidal state is mainly used.

The raw materials of the CMP slurry composition basically contain metal ions, and the degree of the content varies. The content of metal ions affects various performances of the slurry product, and improved performance can be secured by efficiently controlling it.

For example, in the case of aqueous-dispersed colloidal silica, it contains several hundred to several thousand ppm or several ppb levels of metal ions depending on the type of precursor, which is a basic raw material for synthesis. When this is applied to the slurry composition, the content of metal ions included in the additive combined to determine the metal ion level of the composition.

In particular, when colloidal silica prepared using a water glass-based precursor is used as abrasive particles, the aqueous dispersion composition itself contains a high content of metal ions, which itself is the concentration of metal ions in the slurry composition. will raise

Metal ions act as counter ions to improve dispersibility by inducing electrostatic repulsion between nanoparticles on the dispersion medium, but when metal ions are contained above a certain level, dispersibility deteriorates.

In addition, the positively charged metal ions in the slurry composition used in the actual CMP process react with the negatively charged surface of the target film to reduce the electrostatic repulsive force, thereby improving the physical polishing rate. , causing adsorption by chemical bonding between the nanoparticle-film surface and increasing the number of defects after the final CMP process.

Korea Registered Patent No. 0497410

As a result of the research conducted by the present inventors, by controlling the content of polyvalent metal ions as well as the content of total metal ions in the slurry composition, and controlling the ratio of the polishing rate for the silicon oxide film and the copper film to a certain range, the goal It has been found that it is possible to provide a slurry composition capable of reducing the occurrence of defects while ensuring the polishing performance of the present invention.

Accordingly, an object of the embodiment is to provide a CMP slurry composition capable of reducing the occurrence of defects while securing polishing performance, a method of manufacturing the same, and a method of manufacturing a semiconductor device using the same.

According to one embodiment, the total content of metal ions is 5,000 ppmw or less, the content of polyvalent metal ions is less than 1% by weight based on the total content of metal ions, and polishing of the copper film compared to the polishing rate of the silicon oxide film A CMP slurry composition is provided, wherein the ratio is 0.5 to 0.9.

According to another embodiment, the content of the total metal ions in the slurry composition including the abrasive particles is adjusted to be 5,000 ppmw or less, and the content of the polyvalent metal ions is adjusted to be less than 1% by weight based on the content of the total metal ions. A method for preparing a CMP slurry composition is provided, comprising the steps.

According to another embodiment, the method includes chemical mechanical polishing (CMP) of the surface of the semiconductor substrate using a polishing pad and a slurry composition, wherein the slurry composition has a total metal ion content of 5,000 ppmw or less, and a total metal ion content of 5,000 ppmw or less. A method of manufacturing a semiconductor device is provided, wherein the content of polyvalent metal ions is less than 1% by weight based on the content of , and the ratio of the polishing rate for the copper film to the polishing rate for the silicon oxide film is 0.5 to 0.9.

According to the above embodiment, by controlling the content of polyvalent metal ions together with the total content of metal ions in the composition, and controlling the ratio of the polishing rate for the silicon oxide film and the copper film to a certain range, the target polishing performance is secured It is possible to provide a slurry composition capable of reducing the occurrence of defects while doing so.

In addition, such a slurry composition can be easily prepared by selecting a raw material component or reducing or adding a specific metal ion.

Accordingly, the slurry composition may be applied to a semiconductor device manufacturing process including CMP to improve the quality of products including semiconductor substrates.

1 and 2 are results of observing defects generated after the CMP process using the slurry compositions of Examples and Comparative Examples for a copper film and a silicon oxide film, respectively.

In the following description of embodiments, in the case where each layer, pad or sheet, etc. is described as being formed "on" or "under" each layer, pad or sheet, etc., "on ( “on” and “under” include both “directly” or “indirectly” with other elements interposed therebetween.

In addition, the reference for the upper / lower of each component will be described with reference to the drawings. The size of each component in the drawings may be exaggerated for explanation, and does not mean the size actually applied.

In addition, it should be understood that all numerical ranges indicating physical property values, dimensions, etc. of the components described in the present specification are modified by the term "about" in all cases unless otherwise specified.

[Slurry Composition]

In the slurry composition according to an embodiment, the total metal ion content is 5,000 ppmw or less, the polyvalent metal ion content is less than 1 wt % based on the total metal ion content, and the copper film compared to the polishing rate for the silicon oxide film The ratio of the abrasion rate to that is 0.5 to 0.9.

Total metal ion content

The slurry composition contains various metal components.

Such metal ions may be derived from raw materials or impurity components added to the slurry composition. Specifically, the metal ions may be derived from raw materials such as abrasive particles, corrosion inhibitors, chelating agents, and ionic additives, or impurity components contained therein.

For example, the slurry composition may include at least one ion of a metal such as an alkali metal, an alkaline earth metal, a transition metal, a metalloid, a lanthanide metal, or an actinide group metal. Specifically, the slurry composition may include at least one ion of a metal such as Li, Na, K, Mg, Ca, Al, Mn, Fe, Cr, or Ti.

The total content of metal ions in the slurry composition is 5,000 parts per million by weight (ppmw) or less, and when it is within the above range, the number of defects occurring on the surface of the semiconductor substrate during the CMP process may be reduced.

Specifically, the total content of metal ions in the slurry composition may be 4,500 ppmw or less, 4,000 ppmw or less, 3,500 ppmw or less, 3,000 ppmw or less, 2,500 ppmw or less, 2,000 ppmw or less, or 1,500 ppmw or less.

On the other hand, a trace amount of metal ions in the slurry composition may contribute to an increase in CMP performance such as a polishing rate. Specifically, when the surface of the semiconductor substrate is polished using the slurry composition, the film on the surface of the semiconductor substrate may have the same type of electrical charge as the abrasive particles in the slurry composition depending on the type. In this case, the metal ion functions as an intermediate medium, and it is possible to prevent the film on the surface of the semiconductor substrate and the abrasive particles from decreasing in polishing performance due to the mutual repulsion force.

From this point of view, the total content of metal ions in the slurry composition may be 100 ppmw or more, specifically, 200 ppmw or more, 300 ppmw or more, 400 ppmw or more, 500 ppmw or more, or 1,000 ppmw or more.

More specifically, the total metal ion content in the slurry composition is 100 ppmw to 5,000 ppmw, 100 ppmw to 4,000 ppmw, 100 ppmw to 3,000 ppmw, 100 ppmw to 2,000 ppmw, 1,000 ppmw to 5,000 ppmw, 2,000 ppmw to 5,000 ppmw, 3,000 ppmw to 5,000 ppmw, or 4,000 ppmw to 5,000 ppmw.

As a specific example, the total content of metal ions in the slurry composition may be 1,000 ppmw to 4,000 ppmw, and when it is within the above range, it may be more advantageous in terms of reduction of the number of defects occurring on the surface of the semiconductor substrate during the CMP process and improvement of the polishing rate. have.

polyvalent metal ion content

The slurry composition according to the embodiment contains at least one multi-valent metal ion.

The polyvalent metal ion may be derived from a raw material component or impurity components added to the slurry composition.

Specifically, the slurry composition includes, in addition to alkali metal ions such as Li, Na, K, Rb, and Cs, divalent metal ions such as Be, Mg, Ca, Sr, Ba, and Al, V, Co, Ni , Zn, Fe, Cr, and includes a multivalent (multi-valent) metal ion such as a trivalent (trivalent) metal ion of Zr.

Since the polyvalent metal ions in the slurry composition exist as cations such as divalent and trivalent cations, two or more electronic bonds are possible, so it is easy to generate defects on the surface of the semiconductor substrate during the CMP process by exerting a bonding force between heterogeneous components.

Therefore, the content of polyvalent metal ions among the metal ions contained in the slurry composition is important, and according to the above embodiment, it is less than 1% by weight based on the content of the total metal ions in the slurry composition.

Specifically, the content of polyvalent metal ions in the slurry composition may be 0.5 wt% or less, 0.2 wt% or less, or 0.1 wt% or less, based on the total metal ion content.

On the other hand, when the polyvalent metal ion present in the slurry composition is present in an appropriate amount for the reason that two or more electron bonds are possible, it not only improves the dispersibility of the slurry composition but also improves the reactivity between the silicon oxide film surface and the nanoparticles, resulting in CMP It can contribute to an increase in performance.

From this point of view, the content of polyvalent metal ions may be 0.001 wt% or more based on the total metal ion content in the slurry composition, and specifically, 0.01 wt% or more, 0.05 wt% or more, or 0.1 wt% or more.

More specifically, the content of polyvalent metal ions based on the total metal ion content in the slurry composition is 0.001 wt% to 1 wt%, 0.01 wt% to 1 wt%, 0.05 wt% to 0.5 wt%, 0.1 wt% to 0.3 wt% % by weight.

As a specific example, the content of the polyvalent metal ion may be 0.1 wt% to 0.5 wt% based on the total metal ion content in the slurry composition, and when within the range, the number of defects occurring on the surface of the semiconductor substrate during the CMP process It may be more advantageous in terms of reduction of , and improvement of the performance of the CMP process.

constituents of the composition

The CMP slurry composition may include abrasive particles, a corrosion inhibitor, a chelating agent and an ionic additive.

The abrasive particles may include colloidal silica, ceria, alumina, zeolite, titania, zirconia, inorganic composite particles, organic-inorganic composite particles, or a combination thereof, and most preferably colloidal silica, but is not limited thereto.

Specifically, the inorganic composite particles may be particles in which two or more of the aforementioned types of inorganic components are mixed, for example, silica-ceria composite particles, but is not limited thereto.

Specifically, the organic-inorganic composite particle may be a core-shell particle consisting of a core including a polymer resin and a shell including an inorganic component disposed on the surface of the core. For example, the polymer resin of the core may include polymethyl methacrylate (PMMA) resin, polystyrene (PS) resin, and the like, and the inorganic component constituting the shell may include silica, ceria, and the like.

In addition, the CMP slurry composition may include 5 wt% to 20 wt%, 9 wt% to 16 wt%, or 10 wt% to 12 wt% of the abrasive particles based on the total weight. When the abrasive particles are included in less than 5% by weight, it is difficult to achieve the polishing rate and flatness required in the CMP process. may decrease.

Further, in terms of an appropriate polishing rate and dispersion stability of the slurry composition, a 10% cumulative mass particle size distribution diameter D ₁₀ in the particle distribution of the abrasive particles is 40 nm to 70 nm, and a 50% cumulative mass particle size distribution diameter D ₅₀ is 70 nm to 100 nm, 90% cumulative mass particle size distribution diameter D ₉₀ may be 100 nm to 130 nm, more preferably D ₁₀ is 50 nm to 60 nm, and 50% cumulative mass particle size distribution diameter D ₅₀ may be 80 nm to 90 nm, and 90% cumulative mass particle size distribution diameter D ₉₀ may be 110 nm to 120 nm, but is not limited thereto. In addition, it is most preferable that the distribution ratio for each diameter is 1.2 ≤ D ₉₀ /D ₅₀ ≤ 1.5, 1.8 ≤ D ₉₀ /D ₁₀ ≤ 2.4 and/or 1.3 ≤ D ₅₀ /D _{10 ≤ 1.8.}

The corrosion inhibitor may include an azole-based compound, a water-soluble polymer, an organic acid, and the like. For example, by using a combination of an azole compound, a water-soluble polymer, and an organic acid as the corrosion inhibitor, the slurry composition for CMP can secure an appropriate degree of polishing for the target film and greatly improve the surface stability after polishing. .

In addition, in the slurry composition for CMP, the total content of the corrosion inhibitor may be 0.5 parts by weight or less, for example, 0.001 to 0.1 parts by weight, preferably 0.01 to 0.05 parts by weight, based on 100 parts by weight of the abrasive particles. have.

The azole compound is benzotriazole, 5-methyl-1H-benzotriazoletriazole, 3-amino-1,2,4-triazole, 5-phenyl-1H-tetrazole, 3-amino-5-methyl It may include at least one selected from the group consisting of -4H-1,2,4-triazole, 5-aminotetrazole, 1,2,4-triazole, tolytriazole, and combinations thereof, and benzo It is most preferably a triazole, but is not limited thereto.

The water-soluble polymer may include at least one selected from the group consisting of polyvinylpyrrolidone, polyvinyl alcohol, polyethylene glycol, polymethacrylic acid, and combinations thereof, and polyvinylpyrrolidone is most preferred, However, the present invention is not limited thereto.

In particular, the water-soluble polymer may have a weight average molecular weight (Mw) of 2,500 to 100,000, 3,000 to 50,000, and is suitable when it is 3,500 to 10,000. When using Mw of 2,500 or less, it is difficult to obtain sufficient corrosion protection performance, and when Mw of 100,000 or more is used, the dispersibility of the slurry solution may be reduced.

The organic acid may include at least one selected from the group consisting of acetic acid, formic acid, benzoic acid, nicotinic acid, picolinic acid, alanine, glutamic acid, phthalic acid, and combinations thereof, and most preferably, acetic acid, but is not limited thereto.

The slurry composition may include a mixture of an azole compound and a water-soluble polymer as a corrosion inhibitor: an organic acid in a weight ratio of 5: 1 to 1:1, 3: 1 to 1:1, or 2: 1 to 1:1.

In addition, the corrosion inhibitor may include the azole-based compound: the water-soluble polymer in a weight ratio of 5: 1 to 1: 5, 3: 1 to 1: 3, and 2: 1 to 1: 2.

_{The chelating agent may be a compound including four or more -COOH or -NH 2} among functional groups of the compound, and may be used alone or in a mixture of two or more. Examples of the chelating agent include ethylenediaminetetraacetic acid (EDTA), ethylene glycol tetraacetic acid (EGTA), 2,3-dimercapto-1-propanesulfonic acid (DMPS), and alpha lipoic acid (ALA).

The ionic additive may include alkali metal ions and/or polyvalent metal ions as cations, and may include nitrate ions, sulfate ions, phosphate ions, and the like as anions. Examples of the ionic additive include sodium nitrate (NaNO ₃ ), potassium nitrate (KNO ₃ ), thiamine nitrate (C ₁₂ H ₁₇ N ₅ O ₄ S), tetraethylammonium nitrate ((C ₂ H ₅ ) 4N (NO _{3 )} )) sodium sulfate (Na ₂ SO ₄ ), potassium sulfate (K ₂ SO ₄ ), potassium phosphate (KH ₂ PO ₄ ), sodium phosphate (Na ₃ PO ₄ ), trimethylphosphoric acid ((CH ₃ O) ₃ PO), etc. can be heard

The CMP slurry composition may include 0.01 parts by weight to 1 part by weight of the corrosion inhibitor, 0.1 parts by weight to 1 part by weight of the chelating agent, and 0.001 parts by weight to 2 parts by weight of the ionic additive, based on 100 parts by weight of the abrasive particles have.

In addition, the CMP slurry composition may include an aqueous solvent as a dispersion solvent, for example, water, particularly distilled water. The CMP slurry composition may have a solid content of 7 wt% to 28 wt%.

physical properties of the composition

The CMP slurry composition may have a pH value of 8 to 12, 8 to 11, or 9 to 12. When the pH is within the above range, the formation of a copper oxide film through oxidation and reduction reactions of the copper film formed on the surface of the semiconductor substrate may be more advantageous, and hydration with colloidal silica particles due to an increase in the hydroxyl group (-OH) on the surface of the silicon oxide film (hydration) reaction is increased, which is more advantageous for improving the polishing rate.

In addition, the CMP slurry composition may have a conductivity of 4 mS/cm to 10 mS/cm, specifically 4 mS/cm to 8 mS/cm, and more specifically 6 mS/cm to 8 mS/m. When the conductivity is within the above range, the oxidation-reduction reaction of the surface of the copper film may be optimized, and it may be more advantageous to improve the polishing rate of the silicon oxide film. On the other hand, if the conductivity is too high, the corrosion reaction on the surface of the copper film increases, which may cause pit corrosion or a fan phenomenon. If the conductivity is too low, the dispersibility of nanoparticles and the polishing rate of the silicon oxide film reduction may occur.

As a specific example, the CMP slurry composition may have a pH value of 8 to 12, and a conductivity of 4 mS/cm to 10 mS/cm.

abrasion rate

The CMP slurry composition may have a copper film polishing rate of 300 Å/min to 1500 Å/min, 500 Å/min to 1500 Å/min, or 300 Å/min to 1000 Å/min. Specifically, the CMP slurry composition may have a copper film polishing rate of 500 Å/min to 1000 Å/min.

In addition, the CMP slurry composition may have a silicon oxide layer polishing rate of 500 Å/min to 1500 Å/min, 500 Å/min to 1000 Å/min, or 700 Å/min to 1000 Å/min.

The ratio of the polishing rate for the copper film to the polishing rate for the silicon oxide film may be 0.5 to 0.9, 0.5 to 0.8, 0.6 to 0.9, or 0.7 to 0.9. Specifically, the ratio of the polishing rate for the copper film to the polishing rate for the silicon oxide film may be 0.6 to 0.8. When it is within the above range, it may be more advantageous in terms of reducing the step difference between the silicon oxide film and the copper film on the surface of the semiconductor substrate by the CMP process.

[Method for producing slurry composition]

In the method for preparing a slurry composition according to an embodiment, the content of the total metal ions in the slurry composition including the abrasive particles is adjusted to be 5,000 ppmw or less, and the content of the polyvalent metal ions is 1 weight based on the content of the total metal ions. % or less.

The metal ion content may be controlled by a method such as selection of a raw material such as abrasive particles and reduction or addition of metal ions.

For example, the content control of the total metal ions or the polyvalent metal ions may be performed by reducing or adding metal ions, which may be performed by a pre-treatment or post-treatment process.

Specifically, the content control of the total metal ions or the polyvalent metal ions may be performed by addition of a metal ionic compound, adsorption of metal ions, or selection or pretreatment of raw materials containing metal ions.

More specifically, in order to contain more than a certain amount of metal ions in the slurry, it may be performed by adjusting the input content of additives such as metal ionic compounds or by changing the type of dispersant used in the abrasive particles. In addition, in order to control the content of metal ions to a certain level or less, a filter process capable of selectively adsorbing metal ions may be added, or abrasive particles using a polymer material or organic material other than metal ions may be used as a dispersant.

As an example, controlling the content of the total metal ions or the polyvalent metal ions may include adjusting the content of the total metal ions or the polyvalent metal ions contained in the abrasive particles. More specifically, the control of the content of metal ions may be performed by a method including controlling the content of metal ions including polyvalent metal ions through the application of a pretreatment process during the synthesis of colloidal silica particles.

[Method for manufacturing semiconductor device]

A method of manufacturing a semiconductor device according to an embodiment includes polishing a surface of a semiconductor substrate using the slurry composition according to the embodiment.

That is, the method of manufacturing a semiconductor device according to an embodiment includes chemical mechanical polishing (CMP) of the surface of a semiconductor substrate using a polishing pad and a slurry composition, wherein the slurry composition has a total metal ion content of 5,000 ppmw or less, the content of polyvalent metal ions is less than 1 wt% based on the total content of metal ions, and the ratio of the polishing rate for the copper film to the polishing rate for the silicon oxide film is 0.5 to 0.9.

Specifically, after the polishing pad is adhered to the surface plate, a semiconductor substrate is disposed on the polishing pad. In this case, the surface of the semiconductor substrate is in direct contact with the polishing surface of the polishing pad. The slurry composition according to the embodiment is sprayed on the polishing pad for polishing. Thereafter, the semiconductor substrate and the polishing pad may be rotated relative to each other, so that the surface of the semiconductor substrate may be polished.

According to the above embodiment, by controlling the content of polyvalent metal ions together with the total content of metal ions in the composition, and controlling the ratio of the polishing rate for the silicon oxide film and the copper film to a certain range, the target polishing performance is secured It is possible to provide a slurry composition capable of reducing the occurrence of defects while doing so. In addition, such a slurry composition may be prepared by selecting a raw material component or reducing or adding a specific metal ion. Accordingly, the slurry composition may be applied to a semiconductor device manufacturing process including CMP to improve the quality of products including semiconductor substrates.

[Example]

It will be described in more detail through the following examples, but is not limited to the scope of these examples.

Examples and Comparative Examples

Abrasive particles, corrosion inhibitors, chelating agents and ionic additives were added to the dispersion solvent in a composition according to Table 1 below to prepare a slurry composition.

Abrasive particles A: Nano colloidal silica particles containing a dispersant that generates +1 valent counter metal ions in aqueous solution, synthesized after an ion exchange resin process or an electrical adsorption process using water glass as a precursor.

Abrasive particles A': Nano colloidal silica particles containing a dispersing agent that uses water glass as a precursor and does not go through a process of removing metal ions, and generates +1 valent counter metal ions in aqueous solution.

Abrasive particles B: Nano colloidal silica particles that are synthesized using silicon-containing alkoxides as precursors, and contain a trace amount of polymer as a dispersant

Abrasive particles C: Nano colloidal silica particles containing a dispersing agent that generates ^{ammonium ions (NH 4+} ) in aqueous solution, which are synthesized without a process of removing metal ions using water glass as a precursor.

Corrosion inhibitor: azole type, carboxylic acid type

Chelating agent: amino acid type, carboxylic acid type

Ionic additives: alkaline nitric acid, sulfuric acid, phosphoric acid

division abrasive grain
Kinds preservative
(weight%) chelating agent
(weight%) Ionic Additives
(weight%) Example 1 A 0.1 0.7 0.2 Example 2 A 0.1 0.7 0.4 Example 3 A 0.1 0.7 0.6 Example 4 B 0.1 0.7 0.2 Comparative Example 1 A' 0.1 0.7 1.0 Comparative Example 2 A' 0.2 0.7 0.4 Comparative Example 3 C 0.1 0.7 0.4 * Content (% by weight) is based on the total weight of the slurry composition

test example

The polishing pads prepared in Examples and Comparative Examples were tested as follows, and the results are shown in Tables 2 and 3 below.

(1) Determination of metal ion content

The slurry composition was diluted 1000 times and analyzed for metal ions by inductively coupled plasma spectrophotometer (ICP-OES). The results are shown in Table 2 below.

- Total metal ion content: the content of the total metal ion contained in the slurry composition based on the weight of the slurry composition

- Multivalent metal ion content: the total content of divalent metal ions and trivalent metal ions based on the weight of the slurry composition

(2) polishing rate

The polishing rate was evaluated for a semiconductor substrate having a copper film having a thickness of about 15,000 Å and a semiconductor substrate having a silicon oxide film having a thickness of about 20,000 Å. Specifically, 0.2 wt% of hydrogen peroxide (H ₂ O ₂ ) was simultaneously added with each slurry composition, and the pressure was 2.2 psi for 38 seconds, the carrier speed was 103 rpm, the platen speed was 57 rpm, and the slurry flow rate was 300 mL/min. Polishing was performed with After polishing, the thickness of the copper film and the silicon oxide film was measured, and the polishing rate of the slurry composition was calculated from this by the following equation.

Polishing rate (Å/sec) = Change in film thickness by polishing (Å) / Polishing time (sec)

(3) Number of defects

After performing the CMP process in the same manner as in (2) above using the polishing pad sample, a cleaning chemical product of Youngchang Chemical (product name: YC-3100) was used, and the brush rotation speed was 500 rpm, and the chemical spray speed was 2000 cc/ The cleaning process was performed at min. After that, the total number of defects was measured using a defect inspection equipment (AIT XP+, KLA Tencor) in a state in which the semiconductor substrate having the copper film and the semiconductor substrate having the silicon oxide film were sealed in the foup. Table 3 shown in In addition, the results of observing defects generated after the CMP process using the slurry compositions of Examples and Comparative Examples for the copper film and the silicon oxide film are shown in FIGS. 1 and 2 , respectively.

division pH conductivity
(mS/cm) *All metal
Ion (ppmw) * polyvalent metal
Ion (ppmw) Total metal ion contrast
polyvalent metal ion content
(weight%) Example 1 10.3 6.7 2802 5 0.18 Example 2 10.3 7.8 3770 One 0.16 Example 3 10.3 9.3 4332 4 0.09 Example 4 10.3 4.2 980 0 0 Comparative Example 1 10.3 12.1 5727 41 0.72 Comparative Example 2 10.3 7.5 3639 39 1.07 Comparative Example 3 10.3 8.3 3528 272 7.71 * Metal ion content (ppmw) based on the weight of the slurry composition

division Polishing rate (Å/min) abrasion rate number of defects copper film silicon oxide film copper film/
silicon oxide film copper film silicon oxide film Example 1 624 1033 0.60 629 76 Example 2 790 1145 0.69 977 73 Example 3 968 1212 0.80 1173 90 Example 4 633 870 0.73 537 98 Comparative Example 1 1021 1276 0.80 1828 111 Comparative Example 2 432 1225 0.35 1620 112 Comparative Example 3 832 1342 0.62 2551 126

As shown in Tables 2 and 3, the slurry compositions according to Examples 1 to 4 control the content of polyvalent metal ions as well as the content of total metal ions, and set the ratio of the polishing rate to the silicon oxide film and the copper film in a certain range. By controlling the

Claims (12)

The content of the total metal ions is 2,000 ppmw to 5,000 ppmw, the content of polyvalent metal ions is 0.1 to 0.5 wt% based on the content of the total metal ions, and the ratio of the polishing rate for the copper film to the polishing rate for the silicon oxide film is 0.5 to 0.9,
wherein the polyvalent metal ion is at least one divalent metal ion selected from the group consisting of Be, Mg, Ca, Sr and Ba; and one or more trivalent metal ions selected from the group consisting of Al, V, Co, Ni, Zn, Fe, Cr and Zr,
10% cumulative mass particle size distribution diameter D ₁₀ is 40 nm to 70 nm,
50% cumulative mass particle size distribution diameter D ₅₀ is 70 nm to 100 nm,
90% cumulative mass particle size distribution diameter D ₉₀ is between 100 nm and 130 nm,
The CMP slurry composition, wherein the distribution ratio for each diameter is 1.2 ≤ D ₉₀ /D ₅₀ ≤ 1.5, 1.8 ≤ D ₉₀ /D ₁₀ ≤ 2.4 and 1.3 ≤ D ₅₀ /D _{10 ≤ 1.8.}
delete The method of claim 1,
The content of the total metal ions is 2,000 ppmw to 4,000 ppmw, CMP slurry composition.
The method of claim 1,
The polishing rate for the copper film is 500 Å / min to 1000 Å / min, CMP slurry composition.
The method of claim 1,
The ratio of the polishing rate for the copper film to the polishing rate for the silicon oxide film is 0.6 to 0.8, the CMP slurry composition.
The method of claim 1,
wherein the CMP slurry composition has a pH value of 8 to 12, and a conductivity of 4 mS/cm to 10 mS/cm.
The method of claim 1,
wherein the CMP slurry composition comprises abrasive particles, a corrosion inhibitor, a chelating agent and an ionic additive.
8. The method of claim 7,
Compared to 100 parts by weight of the abrasive particles,
0.01 part by weight to 1 part by weight of the corrosion inhibitor;
0.1 part by weight to 1 part by weight of the chelating agent, and
A CMP slurry composition comprising 0.001 parts by weight to 2 parts by weight of the ionic additive.
Controlling the total metal ion content in the slurry composition including the abrasive particles to be 2,000 ppmw to 5,000 ppmw, and adjusting the content of polyvalent metal ions to 0.1 to 0.5 wt% based on the total metal ion content and
wherein the polyvalent metal ion is at least one divalent metal ion selected from the group consisting of Be, Mg, Ca, Sr and Ba; and one or more trivalent metal ions selected from the group consisting of Al, V, Co, Ni, Zn, Fe, Cr and Zr,
10% cumulative mass particle size distribution diameter D ₁₀ is 40 nm to 70 nm,
50% cumulative mass particle size distribution diameter D ₅₀ is 70 nm to 100 nm,
90% cumulative mass particle size distribution diameter D ₉₀ is between 100 nm and 130 nm,
For each diameter, the distribution ratio is 1.2 ≤ D ₉₀ /D ₅₀ ≤ 1.5, 1.8 ≤ D ₉₀ /D ₁₀ ≤ 2.4 and 1.3 ≤ D ₅₀ /D ₁₀ ≤ 1.8, the method for producing a CMP slurry composition.
10. The method of claim 9,
Control of the content of the total metal ions or the polyvalent metal ions
A method for producing a CMP slurry composition, which is performed by addition of a metal ionic compound, adsorption of metal ions, or selection or pretreatment of a raw material containing metal ions.
10. The method of claim 9,
Controlling the content of the total metal ions or the polyvalent metal ions,
A method for producing a CMP slurry composition, comprising adjusting the content of total metal ions or polyvalent metal ions contained in the abrasive particles.
chemical mechanical polishing (CMP) of the surface of the semiconductor substrate using a polishing pad and a slurry composition;
The slurry composition has a total metal ion content of 2,000 ppmw to 5,000 ppmw, a polyvalent metal ion content of 0.1 to 0.5 wt% based on the total metal ion content, and a copper film compared to the polishing rate for the silicon oxide film. The ratio of the polishing rate is 0.5 to 0.9,
wherein the polyvalent metal ion is at least one divalent metal ion selected from the group consisting of Be, Mg, Ca, Sr and Ba; and one or more trivalent metal ions selected from the group consisting of Al, V, Co, Ni, Zn, Fe, Cr and Zr,
10% cumulative mass particle size distribution diameter D ₁₀ is 40 nm to 70 nm,
50% cumulative mass particle size distribution diameter D ₅₀ is 70 nm to 100 nm,
90% cumulative mass particle size distribution diameter D ₉₀ is between 100 nm and 130 nm,
For each diameter, the distribution ratio is 1.2 ≤ D ₉₀ /D ₅₀ ≤ 1.5, 1.8 ≤ D ₉₀ /D ₁₀ ≤ 2.4 and 1.3 ≤ D ₅₀ /D ₁₀ ≤ 1.8.

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