KR20160077645A - Slurry composition for chemical mechanical polishing and method for manufacturing semiconductor device by using the same - Google Patents

Abstract

The present invention relates to a slurry composition for chemical mechanical polishing, which comprises: 0.1-10 wt% of a polishing material; 0.01-1 wt% of a polishing surface modifier selected from the group consisting of ethylenediamine tetraacetic acid, diethylenetriamine pentaacetic acid, and a salt and a combination thereof; 0.01-1 wt% of a polishing modifier selected from the group consisting of an aromatic carboxylic acid and a salt and a combination thereof; and the balance of a solvent, and a method for manufacturing a semiconductor device using the same. According to the present invention, it is possible to control a polishing rate of cobalt freely to obtain an effective high-quality polished surface. It is also possible to carry out polishing of copper, cobalt and a low-dielectric constant dielectric layer at the same time to avoid unbalanced polishing, dishing or erosion caused by a difference in polishing rate. Further, it is possible to provide excellent characteristics free from surface pitting defects or corrosion after polishing.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a chemical mechanical polishing slurry composition, and a method of manufacturing a semiconductor device using the same. BACKGROUND OF THE INVENTION [0002]

The present invention relates to a chemical mechanical polishing slurry composition and a method of manufacturing a semiconductor device using the same. More particularly, the present invention relates to a polishing slurry composition for polishing a copper, cobalt and low dielectric constant insulating film A chemical mechanical polishing slurry composition which does not cause abrasion unevenness, dishing or erosion due to polishing rate difference and has good properties without pitting defects or corrosion on the surface after polishing, and And a method of manufacturing a semiconductor device using the same.

Chemical mechanical polishing (CMP) is one of the methods commonly used for surface planarization. In the chemical mechanical polishing (CMP) process, a wafer to be subjected to a planarization process is placed on a rotating plate, the surface of the wafer is brought into contact with the pad of the polishing machine, and then the pad of the rotating plate and the polishing machine is rotated Thereby performing a polishing process. That is, the slurry flows between the surface of the wafer and the pad, and the surface of the wafer is polished by the mechanical friction caused by the abrasive particles in the slurry and the surface protrusions of the pad, and chemical removal is performed by chemical reaction between the chemical components in the slurry and the wafer surface .

In general, tantalum is used as a metal barrier material in a copper wiring process. However, as the wiring width becomes smaller, there is an increasing need for a substitute material having a lower resistivity than tantalum and having excellent adhesion to copper. Cobalt is the most likely alternative material for tantalum. Cobalt is not only lower in resistivity than tantalum, but also has many advantages such as easy nucleation of copper on cobalt, excellent adhesion to copper, and low cost.

The slurry used for the chemical mechanical polishing of the copper wiring process uses a colloidal silica abrasive and is characterized by the removal of the barrier metal and the oxide film in the basic region. However, the basic slurry has a high problem of particle contamination and scratching after polishing.

To solve this problem, chemical mechanical polishing slurries have been developed which act in the acidic region. However, the acidic slurry has a problem in that corrosion of copper and cobalt is significant and the polishing rate is increased, causing dishing and erosion, and occurrence of defects on the polishing surface is increased.

Korean Laid-Open Patent No. 2014-0117622 (Published Oct. 10, 2014) Korean Patent Publication No. 2010-0118246

The object of the present invention is to provide a polishing composition which can freely control the polishing rate of cobalt and can simultaneously polish copper, cobalt and a low dielectric constant insulating film, does not cause polishing unbalance, dishing or erosion due to polishing speed difference, Provided is a chemical mechanical polishing slurry composition capable of obtaining an effective high-quality polished surface because there is no defect or corrosion on the back surface, excellent stability over time and dispersion stability, and low occurrence of particles and scratch defects, and a method for manufacturing a semiconductor device using the same .

One embodiment of the present invention for solving the above problems is a polishing pad comprising: 0.1 to 10% by weight of an abrasive; From 0.01 to 1% by weight of an abrasive surface modifier selected from the group consisting of ethylenediamine tetraacetic acid, diethylenetriamine pentaacetic acid, its salts and combinations thereof; From 0.01 to 1% by weight of an abrasive modifier selected from the group consisting of aromatic carboxylic acids, salts thereof, and combinations thereof; And a remainder of the solvent.

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device using a chemical mechanical polishing slurry composition according to an embodiment of the present invention, And a step of polishing the single film.

The chemical mechanical polishing slurry composition of the present invention can simultaneously remove copper, cobalt, and low dielectric constant insulating film under acidic conditions, and does not cause polishing unbalance, dishing or erosion due to the difference in polishing rate.

In addition, the chemical mechanical polishing slurry composition of the present invention can freely control the polishing rate of cobalt, so that an effective high-quality polishing surface can be obtained, and the surface after polishing has a very good feature without any fitting defects or corrosion.

In addition, the chemical mechanical polishing slurry composition of the present invention is advantageous in that the abrasive grains are very small, so that the stability of the aging and the dispersion stability are excellent, the generation of particles and the frequency of scratch defects are low, and the polishing surface of the barrier metal and the low dielectric constant insulating film is very good.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, numerous specific details are set forth, such as specific elements, which are provided to aid a more thorough understanding of the present invention, and it is to be understood that the present invention may be practiced without these specific details, It will be obvious to those who have. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

One embodiment of the present invention provides a polishing composition comprising: 0.1 to 10% by weight of an abrasive; From 0.01 to 1% by weight of an abrasive surface modifier selected from the group consisting of ethylenediamine tetraacetic acid, diethylenetriamine pentaacetic acid, its salts and combinations thereof; From 0.01 to 1% by weight of an abrasive modifier selected from the group consisting of aromatic carboxylic acids, salts thereof, and combinations thereof; And the remainder of the solvent.

The abrasive included in the chemical mechanical polishing slurry composition of the present invention may be colloidal silica.

In one form, acidic colloidal silica may be used as the abrasive. The production method of the acidic colloidal silica is not particularly limited and can be produced, for example, by reacting an alkali metal silicate solution with an inorganic acid, passing the solution through a strongly acidic cation exchange resin, or hydrolyzing a high purity alkoxysilane.

In one form, the colloidal silica may have an average particle size of 5-120 nm, preferably 20-100 nm. When the average particle size of the colloidal silica is less than 5 nm, it is difficult to achieve a desired polishing rate, and when the average particle size exceeds 120 nm, it may be difficult to maintain the stability of the abrasive.

The abrasive may comprise from 0.1 to 10% by weight, preferably from 5 to 10% by weight, based on the total weight of the chemical mechanical polishing slurry composition. When the content of the abrasive is less than 0.1% by weight, it is difficult to achieve a desired polishing rate, and when it exceeds 10% by weight, particle defects may increase.

The polishing surface modifier contained in the chemical mechanical polishing slurry composition of the present invention can play a role of suppressing the occurrence of surface fitting or corrosion after the polishing process for the cobalt film and improving the surface condition.

In one form, the abrasive surface modifier may be selected from the group consisting of ethylenediamine tetraacetic acid, diethylenetriamine pentaacetic acid, its salts, and combinations thereof.

The polishing surface modifier may be included in an amount of 0.1 to 10% by weight, preferably 0.2 to 8% by weight, based on the total weight of the chemical mechanical polishing slurry composition. When the content of the polishing surface modifier is less than 0.1% by weight, it is difficult to obtain the effect of controlling the polishing rate of the cobalt film, so that the surface state can not be maintained satisfactorily. If it exceeds 10% by weight, fitting defects or surface corrosion may occur.

The polishing regulator contained in the chemical mechanical polishing slurry composition of the present invention can freely and freely control the polishing rate of the cobalt film to prevent the generation of scratches and particle defects.

The abrasive modifier may be selected from the group consisting of aromatic carboxylic acids, salts thereof, and combinations thereof.

In one form, the abrasive modifier is selected from the group consisting of:

[Chemical Formula 1]

Wherein at least one of R1, R2, R3, R4, R5 and R6 is a carboxyl group.

, A salt thereof, and a combination thereof.

In one form, the abrasive modifier may be included in an amount of 0.01 to 1% by weight, preferably 0.05 to 0.5% by weight, based on the total weight of the chemical mechanical polishing slurry composition. When the content of the polishing regulator is less than 0.01%, it may be difficult to control the polishing of the cobalt film. If the content of the polishing regulator is more than 1% by weight, the cobalt film may not be polished.

The chemical mechanical polishing slurry composition of the present invention may have a pH value of from 2 to 5. When the pH of the chemical mechanical polishing slurry composition is within the above range, the polishing rate of the cobalt film can be effectively controlled, the copper film, the cobalt film and the low dielectric constant insulating film can be simultaneously removed from the acidic region, have. However, when the pH of the chemical mechanical polishing slurry composition is less than the above range, effective control of the polishing rate is impossible and the corrosion resistance is increased. If the pH exceeds the above range, the polishing rate of the cobalt decreases, Which may cause a problem in stability.

In one form, the chemical mechanical polishing slurry composition of the present invention may further comprise a corrosion inhibitor.

The corrosion inhibitor is selected from the group consisting of 1,2,4-triazole, benzotriazole, 5-methyl-benzotriazole, 5-aminotetrazole, 1-alkyl- Alkyl-5-hydroxy-tetrazole, tetrazole-5-thiol, imidazole, and combinations thereof.

The corrosion inhibitor may be included in an amount of 0.001 to 0.5% by weight based on the total weight of the chemical mechanical polishing slurry composition. When the content of the corrosion inhibitor is less than 0.001% by weight, the corrosion inhibiting effect is difficult to exhibit. When the content exceeds 0.5% by weight, there is a problem in controlling the polishing rate of the cobalt film. There is a concern.

In one form, the chemical mechanical polishing slurry composition of the present invention may further comprise an oxidizing agent.

The oxidizing agent may preferably be selected from the group consisting of hydrogen peroxide, monopersulfate, dipersulfate, and combinations thereof.

Examples of oxidizing agents usable in addition to the above include hydrogen peroxide addition products such as urea hydrogen peroxide or percarbonate, organic peroxides such as benzoyl peroxide, peracetic acid or di-t-butyl peroxide, sodium peroxides, , Perborate, peranganate, or bromate, chromate, iodate, iodic acid, cerium (IV) compound, ferric nitrate, and the like.

The oxidizing agent may be included in an amount of 0.001 to 5% by weight based on the total weight of the chemical mechanical polishing slurry composition. If the content of the oxidizing agent is less than 0.001% by weight, scratches may be generated on the surface of the metal film and the surface performance may be deteriorated. If it exceeds 5% by weight, the stability of the slurry composition may be deteriorated.

In one form, the chemical mechanical polishing slurry composition of the present invention may further comprise a pH adjusting agent.

As the pH regulator which can be added to control the pH of the slurry composition, a basic compound or an acidic compound can be used.

Examples of basic compounds include, but are not limited to, those selected from the group consisting of potassium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, and combinations thereof . Examples of the acidic compound include, but are not limited to, those selected from the group consisting of nitric acid, hydrochloric acid, sulfuric acid, perchloric acid, phosphoric acid, and combinations thereof.

The solvent included in the chemical mechanical polishing slurry composition of the present invention is not particularly limited as long as it is used in a slurry composition for chemical mechanical polishing, and typical examples thereof include, but not limited to, deionized water.

In addition, in one form, the chemical mechanical polishing slurry composition of the present invention may further comprise, if necessary, additives such as anionic surfactant, cationic surfactant, surfactant including nonionic surfactant, antifoaming agent and the like.

Meanwhile, another embodiment of the present invention is a method of polishing a film selected from the group consisting of a copper film, a cobalt film, a low dielectric constant insulating film, and combinations thereof using a chemical mechanical polishing slurry composition according to an embodiment of the present invention The present invention relates to a method of manufacturing a semiconductor device.

The low dielectric constant insulating film may be made of an oxide such as silicon oxide or a porous carbon doped oxide, but is not limited thereto.

In one aspect, the method of fabricating a semiconductor device of the present invention can include simultaneously polishing a copper film, a cobalt film, and a low dielectric constant insulating film using a chemical mechanical polishing slurry composition according to an embodiment of the present invention.

The use of the chemical mechanical polishing slurry composition according to the present invention enables simultaneous removal of copper, cobalt and low dielectric constant insulating film under acidic conditions, thereby suppressing the occurrence of polishing unbalance, dishing and erosion due to the difference in polishing rate, Excellent characteristics can be obtained. Further, the polishing slurry composition of the present invention has very good characteristics that no surface fitting or corrosion occurs after the polishing of the cobalt thin film, and the abrasive grains are very small, so that the stability and stability of aging are excellent and the occurrence of particles and scratch defects are low The polishing surface of the barrier metal and the low dielectric constant insulating film can have a very good advantage.

Hereinafter, the present invention will be described in more detail by way of examples. However, the following examples are illustrative of the present invention, and the scope of the present invention is not limited to the following examples.

[ Experimental Example ]

1. Experimental Method

The thickness of the copper wafer (electroplating) used in the polishing was 10,000 Å, the thickness of the tantalum wafer (PVD) was 3,000 Å, the thickness of the covalent wafer (PVD) was 3,000 Å and the thickness of the low dielectric constant insulating film (Black diamond II) A thin film was used.

Polishing test was performed using H7000HN-PET (Fuji Bossa) and polishing conditions were 93/87 rpm (table / head) , A polishing pressure of 1 psi, a slurry supply flow rate of 250 ml / min, and a polishing time of 30 seconds to 60 seconds.

The thickness of the thin film was measured using a 4-point surface resistance meter (Four Point Probe, NAPSON) after the sheet resistance was measured. The thickness of the PETEOS and silicon nitride films was measured with SpectraTick ST5000 (K-MAC, Spectra Thick ST5000).

0.07% by weight of hydrogen peroxide was added at the time of all polishing evaluations, and polishing evaluation was carried out.

2. Experimental Example  One

After the polishing slurry composition was prepared with the composition shown in Table 1 below, the polishing slurry composition thus prepared was subjected to polishing evaluation, and the results are shown in Table 1.

The abrasives shown in Table 1 were colloidal silica abrasives having a size of 42 nm and were used in the polishing slurry composition in an amount of 2% by weight. When preparing the slurry, nitric acid and potassium hydroxide were used as needed to adjust the pH to the desired value. BTA in Table 1 represents benzotriazole.

pH Abrasive
Size (nm) Abrasive
Content (% by weight) BTA
(weight%) Cu RR
(Å / min) Ta RR
(Å / min) Co RR
(Å / min) low-k RR
(Å / min) Example 1-1 2.3 45 2 0.03 552 332 3677 576 Examples 1-2 2.8 45 2 0.03 565 360 2419 538 Example 1-3 3.5 45 2 0.03 537 347 1740 478 Examples 1-4 4.2 45 2 0.03 398 167 1316 431

Referring to Table 1, it can be seen that as the pH of the slurry increases, the cobalt polishing rate decreases and the polishing rate of the low dielectric constant insulating film also decreases.

3. Experimental Example  2

The additives shown in Table 2 were added to the composition of Example 1-2 in Table 1 in an amount of 0.05% by weight, and the resultant was immersed at 65 캜 for 3 minutes. The result was converted into the etching rate per minute and the state of the etched surface was visually observed The results are shown in Table 2 below. A composition to which the additive is not added in the composition of Example 1-2 is described as Reference Example 1-2.

additive Etch rate
(Å / min) Surface condition Reference Example 1-2 - 337 Worse Example 2-1 5-methyl-1H-benzotriazole 266 Worse Example 2-2 5-Aminotetrazole 345 Worse Example 2-3 2-methylimidazole 242 Sustained Examples 2-4 Benzotriazole 381 Worse Example 2-5 1,2,3-triazole 373 Worse Examples 2-6 Imidazole 336 Worse Examples 2-7 2,6-dihydroxybenzoic acid 282 Sustained Examples 2-8 Ethylenediamine tetraacetic acid 211 Sustained Examples 2-9 Diethylene triamine pentaacetic acid 189 Sustained Comparative Example 2-1 Piperazine 346 Worse Comparative Example 2-2 1,4-dimethylpiperazine 326 Worse Comparative Example 2-3 1-methylpiperazine 333 Worse Comparative Example 2-4 Hexamethylenediamine 335 Worse Comparative Example 2-5 Ethylenediamine 373 Worse Comparative Example 2-6 N, N, N ', N'-tetramethylethylenediamine 319 Worse Comparative Example 2-7 Polyethylene glycol 322 Worse Comparative Example 2-8 Polyvinylpyrrolidone 335 Worse Comparative Example 2-9 Glycine 221 Sustained Comparative Example 2-10 Glutamic acid 208 Sustained Comparative Example 2-11 Aspartic acid 193 Sustained Comparative Examples 2-12 Alanine 260 Worse Comparative Example 2-13 Arginine 233 Sustained

As shown in Table 2, depending on the type of additive added, the surface state of some additives was maintained without color change, while the surface of the etched surface was changed to black due to some additive.

4. Experimental Example  3

In the examples shown in Table 2, the compositions of Examples 2-8 and 2-9 and Comparative Examples 2-9 and 2-10, in which the surface state was maintained without discoloration after etching, were selected to perform the polishing evaluation. Are shown in Table 3 below. For comparison, the composition of Example 1-2, to which no additive is added, is described in Reference Example 1-2.

Hydrogen peroxide (% by weight) Cu RR
(Å / min) Ta RR
(Å / min) Co RR
(Å / min) low-k RR
(Å / min) After polishing
Surface condition Reference Example 1-2 0.07 280 327 1935 625 Fitting occurrence Examples 2-8 0.07 261 340 1939 523 Good Examples 2-9 0.07 314 454 1755 557 Good Comparative Example 2-9 0.07 183 386 2411 343 Surface corrosion Comparative Example 2-10 0.07 236 378 1997 387 Fitting occurrence

As shown in Table 3, in Comparative Example 2-9 and Comparative Example 2-10 in which the additive was not added and Comparative Example 1-2 in which glicin and glutamic acid were added, the polishing rate of the cobalt film was very high, Corrosion occurred. On the other hand, in Examples 2-8 and 2-9 in which ethylenediaminetetraacetic acid and diethylenetriamine pentaacetic acid were respectively added, surface defects and corrosion phenomena did not occur and it was confirmed that the surface state after polishing was satisfactory .

5. Experimental Example  4

The compositions of Examples 2-9 shown in Table 3 above were selected and the additives shown in Table 4 below were added in connection with controlling the cobalt removal rate to prepare slurry compositions. The polishing slurry composition was subjected to polishing evaluation, and the results are shown in Table 4 below. The addition of additives for controlling the cobalt removal rate to the compositions of Examples 2-9 shown in Table 3 is described in Reference Examples 2-9.

additive content
(weight%) Cu RR
(Å / min) Ta RR
(Å / min) Co RR
(Å / min) low-k RR
(Å / min) Reference Example 2-9 Not added 0 314 454 1755 557 Comparative Example 4-1 Glutaric acid 0.5 250 364 1867 477 Example 4-1 Benzene tetracarboxylic acid 0.5 189 448 719 543 Comparative Example 4-2 Poly (acrylic acid-co-maleic acid) 0.5 233 507 1360 465 Comparative Example 4-3 Acetic acid 0.5 162 315 1746 396 Comparative Example 4-4 Propionic acid 0.5 312 261 2311 362 Comparative Example 4-5 Suche mountain 0.5 183 290 1734 434 Comparative Example 4-6 Citric acid 0.5 264 313 1501 443 Comparative Example 4-7 Tartaric acid 0.5 307 421 2102 361

As shown in Table 4, the composition of Example 4-1, that is, the slurry composition to which diethylene triamine pentaacetic acid and benzene tetracarboxylic acid were added, was able to effectively control the cobalt polishing rate, and the surface state after polishing Showed very good condition.

From the experimental results shown in Tables 1 to 4, the chemical mechanical polishing slurry composition comprising the polishing surface modifier and the polishing agent according to the present invention can freely and freely control the polishing rate of cobalt, and the surface defect or corrosion phenomenon . Further, the chemical mechanical polishing slurry composition according to the present invention can simultaneously remove copper, cobalt, and low dielectric constant insulating film, and does not cause polishing unbalance, dishing, erosion, or the like due to the difference in polishing rate, Has a low characteristic.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments or constructions. Various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the invention. It will be clear to those who have knowledge.

Claims (12)

0.1 to 10% by weight of abrasive;
From 0.01 to 1% by weight of an abrasive surface modifier selected from the group consisting of ethylenediamine tetraacetic acid, diethylenetriamine pentaacetic acid, its salts and combinations thereof;
From 0.01 to 1% by weight of an abrasive modifier selected from the group consisting of aromatic carboxylic acids, salts thereof, and combinations thereof; And
Lt; RTI ID = 0.0 >
Chemical mechanical polishing slurry composition.
The method according to claim 1,
Characterized in that the abrasive is a colloidal silica
Chemical mechanical polishing slurry composition.
The method according to claim 1,
Wherein the aromatic carboxylic acid is represented by the following Formula 1:
[Chemical Formula 1]

Wherein at least one of R1, R2, R3, R4, R5 and R6 is a carboxyl group.
Lt; RTI ID = 0.0 >
Chemical mechanical polishing slurry composition.
The method according to claim 1,
Characterized in that the chemical mechanical polishing slurry composition further comprises 0.001 to 0.5% by weight of a corrosion inhibitor
Chemical mechanical polishing slurry composition.
5. The method of claim 4,
The corrosion inhibitor may be selected from the group consisting of 1,2,4-triazole, benzotriazole, 5-methyl-benzotriazole, 5-aminotetrazole, 1-alkyl-5-aminotetrazole, 5-hydroxy- -Alkyl-5-hydroxy-tetrazole, tetrazole-5-thiol, imidazole and combinations thereof.
Chemical mechanical polishing slurry composition.
The method according to claim 1,
Characterized in that said chemical mechanical polishing slurry composition further comprises 0.001 to 5% by weight of an oxidizing agent
Chemical mechanical polishing slurry composition.
The method according to claim 6,
Wherein the oxidizing agent is selected from the group consisting of hydrogen peroxide, monopersulfate, dipersulfate, and combinations thereof.
Chemical mechanical polishing slurry composition.
The method according to claim 1,
Characterized in that the chemical mechanical polishing slurry composition further comprises a pH adjusting agent
Chemical mechanical polishing slurry composition.
9. The method of claim 8,
Wherein the pH adjusting agent is selected from the group consisting of potassium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, nitric acid, hydrochloric acid, sulfuric acid, perchloric acid, phosphoric acid, Characterized by
Chemical mechanical polishing slurry composition.
The method according to claim 1,
Characterized in that the chemical mechanical polishing slurry composition has a pH of from 2 to 5
Chemical mechanical polishing slurry composition.
A method for polishing a semiconductor wafer, comprising polishing a film selected from the group consisting of a copper film, a cobalt film, a low dielectric constant insulating film, and combinations thereof using the chemical mechanical polishing slurry composition according to any one of claims 1 to 10 A method of manufacturing a semiconductor device.
12. The method of claim 11,
Characterized in that the method comprises simultaneously polishing the copper film, the cobalt film and the low dielectric constant insulating film
A method of manufacturing a semiconductor device.