KR102533083B1 - Chemical mechanical polishing slurry composition of wafer contaning poly-silicon - Google Patents

Abstract

The present invention relates to a polishing slurry composition for a wafer containing polysilicon, and more specifically, to a polishing slurry composition comprising: abrasive particles; A polysilicon polishing control agent containing an amine-based compound containing a benzene group; and polysilicon surface improving agents; It relates to a polishing slurry composition for a wafer containing polysilicon, comprising:

Description

Wafer polishing slurry composition containing polysilicon

The present invention relates to a polishing slurry composition for wafers containing polysilicon.

As semiconductor devices are diversified and highly integrated, finer pattern formation technology is being used, and accordingly, the surface structure of semiconductor devices is becoming more complex and the level difference between surface films is getting larger. In manufacturing semiconductor devices, a chemical mechanical polishing (CMP) process is used as a planarization technique for removing steps in a specific film formed on a wafer. CMP compositions are selective in removing one type of integrated circuit component over another. Compositions and methods for CMP of wafer surfaces are well known in the art. CMP slurry compositions for polishing semiconductor wafer surfaces typically include abrasive particles, various additive compounds, and the like. Flash memory devices having three-dimensional transistor stacks (3D flash memory) are increasingly popular. CMP slurry compositions for 3D flash applications should generally provide polysilicon polishing rates, silicon oxide polishing selectivity, as well as good surface topography and low defect levels.

The present invention is to solve the above problems, and an object of the present invention is to provide a polishing slurry composition for a wafer containing polycrystalline silicon having a high polishing rate for polypolycrystalline silicon.

However, the problem to be solved by the present invention is not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

One aspect of the present invention is

abrasive particles; A polysilicon polishing control agent containing an amine-based compound containing a benzene group; and polysilicon surface improving agents; It relates to a polishing slurry composition for a wafer containing polysilicon, comprising:

According to one embodiment of the present invention, the amine-based compound containing a benzene group is phenylethylamine, phenethylamine, methoxyphenethylamine, aminopropylaniline, benzylamine (Bebzylamine), Dibenzylamine, N-Methylbenzylamine, Dimethylbenzylamine, 4-Benzylpiperidine, Dibenzylethanolamine, Tri It may include at least one selected from the group consisting of benzylamine (Tribenzylamine) and ethylcyclohexylamine (Ethylcyclohexylamine).

According to one embodiment of the present invention, the polysilicon polishing control agent may be 0.0001% to 1% by weight of the polishing slurry composition of the wafer containing the polysilicon.

According to one embodiment of the present invention, the polysilicon surface improving agent includes an organic acid, an inorganic acid, or both, and the organic acid is citric acid, malic acid, maleic acid, malonic acid, oxalic acid, succinic acid, lactic acid, tartaric acid, and adip. Acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, acetic acid, adipic acid, butyric acid, capric acid, caproic acid, caprylic acid, glutaric acid, glycolic acid, formic acid, la It contains at least one selected from the group consisting of uric acid, myristic acid, palmitic acid, phthalic acid, propionic acid, pyruvic acid, stearic acid and valeric acid, wherein the inorganic acid is sulfuric acid, nitric acid, phosphoric acid, silicic acid, hydrofluoric acid, boric acid, At least one selected from the group consisting of hydrobromic acid, iodic acid, hydrochloric acid and perchloric acid may be included.

According to one embodiment of the present invention, the polysilicon surface improving agent may be 0.001% to 2% by weight of the polishing slurry composition of the wafer containing the polysilicon.

According to one embodiment of the present invention, a pH adjusting agent comprising an acidic substance or a basic substance; further comprising, wherein the acidic substance is, nitric acid, hydrochloric acid, phosphoric acid, sulfuric acid, hydrofluoric acid, hydrobromic acid, iodic acid, formic acid, malonic acid , maleic acid, oxalic acid, acetic acid, adipic acid, citric acid, adipic acid, acetic acid, propionic acid, fumaric acid, lactic acid, salicylic acid, pimelic acid, benzoic acid, succinic acid, phthalic acid, butyric acid, glutaric acid, glutamic acid, glycolic acid, lactic acid, It includes at least one selected from the group consisting of aspartic acid, tartaric acid, and salts thereof, and the basic material is ammonia, ammonium methyl propanol (AMP), tetramethyl ammonium hydroxide (TMAH) , Ammonium hydroxide, potassium hydroxide, sodium hydroxide, magnesium hydroxide, rubidium hydroxide, cesium hydroxide, sodium hydrogen carbonate, sodium carbonate, imidazole and salts thereof may include at least one selected from the group consisting of.

According to an embodiment of the present invention, the abrasive particles include at least one selected from the group consisting of metal oxides, metal oxides coated with organic or inorganic materials, and the metal oxides in a colloidal state, and the metal oxides It may include at least one selected from the group consisting of silica, ceria, zirconia, alumina, titania, barium titania, germania, mangania, and magnesia.

According to one embodiment of the present invention, the abrasive particles may be surface-substituted with a carboxyl group, a sulfone group, or both.

According to one embodiment of the present invention, the abrasive particles may include particles having a single size of 10 nm to 100 nm or mixed particles having two or more different sizes of 10 nm to 100 nm.

According to one embodiment of the present invention, the abrasive particles may be 0.1% to 10% by weight of the polishing slurry composition of the wafer containing the polysilicon.

According to one embodiment of the present invention, the pH of the polishing slurry composition for the wafer containing polysilicon may be in the range of 4 to 10.

According to one embodiment of the present invention, the polishing rate for the polysilicon film may be 1 Å/min to 3000 Å/min.

The present invention can provide a polishing slurry composition for a wafer containing polycrystalline silicon having a high removal rate for polycrystalline silicon and amorphous silicon by applying a polysilicon polishing control agent containing an amine-based compound containing a benzene group.

Hereinafter, embodiments of the present invention will be described in detail. In describing the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, the terms used in this specification are terms used to properly express preferred embodiments of the present invention, which may vary according to the intention of a user or operator or customs in the field to which the present invention belongs. Therefore, definitions of these terms will have to be made based on the content throughout this specification.

Throughout the specification, when a certain component is said to "include", it means that it may further include other components without excluding other components unless otherwise stated.

Hereinafter, a polishing slurry composition for a wafer containing polysilicon according to an embodiment will be described in detail with reference to Examples. However, the present invention is not limited to these examples.

The present invention relates to a polishing slurry composition for a wafer containing polysilicon, and according to an embodiment of the present invention, the present invention includes abrasive particles; Polysilicon polishing control agent; It is possible to provide a polishing slurry composition for a wafer containing polycrystalline silicon, including; and a polysilicon surface improving agent.

As an example of the present invention, the polishing slurry composition for a wafer containing polycrystalline silicon may be useful for polishing a wafer including at least one selected from the group consisting of a polycrystalline silicon film, an amorphous silicon film, and an oxide film.

As an example of the present invention, the polysilicon film may be any suitable polysilicon material known in the art. For example, polysilicon may exist in any suitable phase, and may be amorphous, crystalline, or combinations thereof. The silicon oxide film may be any suitable silicon oxide material known in the art. For example, tetraethyl orthosilicate (TEOS), plasma-etched tetraethyl orthosilicate (PETEOS), phosphor silicate glass (PSG), boron silicate glass ( boron silicate glass (BSG), boro-phospho silicate glass (BPSG), thermal oxide and undoped silicate glass (USG), high density plasma; HDP oxide).

As an example of the present invention, the abrasive particles may include a metal oxide; metal oxides coated with organic and/or inorganic materials; and the metal oxide in a colloidal state; and the metal oxide is one selected from the group consisting of silica, ceria, zirconia, alumina, titania, barium titania, germania, mangania, and magnesia. May include more than one species. For example, the abrasive particles may be silica; silica coated with organic and/or inorganic materials; and colloidal silica.

For example, the abrasive particles may be surface-substituted with a carboxyl group, a sulfone group, or both. For example, 1 to 20 parts by weight based on 100 parts by weight of the abrasive particles may be used for surface replacement in order to uniformly mix in the slurry composition and improve the softness of the polycrystalline silicon.

For example, the abrasive particles may include those produced by a liquid phase method. The liquid phase method is a sol-gel method in which abrasive particle precursors undergo a chemical reaction in an aqueous solution and crystals are grown to obtain fine particles, a coprecipitation method in which abrasive particle ions are precipitated in an aqueous solution, and abrasive particles are formed under high temperature and high pressure. It can be prepared by applying a hydrothermal synthesis method or the like.

For example, the abrasive particles may be particles having a single size of 10 nm to 100 nm or mixed particles having two or more different sizes of 10 nm to 100 nm. Preferably, it may be 30 nm to 60 nm. When the size of the abrasive particles is less than 10 nm, the polishing rate may be reduced, and when the size is greater than 100 nm, excessive polishing may occur, and dishing, erosion, and surface defects may occur. The size of the abrasive particles can be measured by SEM analysis or dynamic light scattering.

For example, the abrasive particles have a bimodal particle size distribution in which particles having two different sizes are mixed, or particles having three different sizes are mixed and exhibit three peaks. It may have a particle size distribution. By mixing relatively large abrasive particles and relatively small abrasive particles, it has better dispersibility and an effect of reducing scratches on the wafer surface can be expected.

For example, the abrasive particles may be 0.1% to 10% by weight of the polishing slurry composition of the wafer containing the polysilicon. If the abrasive particles are less than 0.1% by weight of the polishing slurry composition of the wafer containing the polysilicon, there is a problem that the polishing rate is reduced, and if it is more than 10% by weight, the polishing rate is too high, and the number of abrasive particles increases. Surface defects may be generated by the remaining adsorption of particles.

As an example of the present invention, the polycrystalline silicon polishing control agent may include an amine-based compound containing a benzene group, which can improve the polishing rate of polycrystalline silicon, amorphous silicon, and the like, compared to conventional amine-based compounds.

For example, the amine-based compound containing the benzene group is phenylethylamine, phenethylamine, methoxyphenethylamine, aminopropylaniline, benzylamine, Benzylamine, N-Methylbenzylamine, Dimethylbenzylamine, 4-Benzylpiperidine, Dibenzylethanolamine, Tribenzylamine , and at least one selected from the group consisting of ethylcyclohexylamine.

For example, the polysilicon polishing control agent may be 0.0001 wt% to 1 wt% of the polishing slurry composition of the wafer containing the polysilicon. If the polysilicon polishing control agent is less than 0.0001% by weight in the polishing slurry composition of the wafer containing polysilicon, the effect of improving the polishing rate of polysilicon cannot be obtained, and if it is more than 1% by weight, the dispersion stability of the slurry composition is lowered and polishing There is a problem in that surface defects occur due to adsorption between particles.

As an example of the present invention, the polysilicon surface improving agent may include an organic acid, an inorganic acid, or both.

For example, the polysilicon surface improving agent, the organic acid, citric acid, malic acid, maleic acid, malonic acid, oxalic acid, succinic acid, lactic acid, tartaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid , maleic acid, fumaric acid, acetic acid, adipic acid, butyric acid, capric acid, caproic acid, caprylic acid, glutaric acid, glycolic acid, formic acid, lauric acid, myristic acid, palmitic acid, phthalic acid, propionic acid, It may include at least one selected from the group consisting of pyruvic acid, stearic acid and valeric acid. In addition, the polysilicon surface improving agent may include at least one selected from the group consisting of the inorganic acid, sulfuric acid, nitric acid, phosphoric acid, silicic acid, hydrofluoric acid, boric acid, hydrobromic acid, iodic acid, hydrochloric acid, and perchloric acid.

For example, the crystalline silicon surface improving agent may be 0.1% to 2% by weight of the polishing slurry composition of the wafer containing the polysilicon. When the polysilicon surface improving agent is less than 0.1% by weight, the polishing rate of the polysilicon film may be lowered, and when it is greater than 2% by weight, dispersion stability is lowered, resulting in surface defects such as scratches.

As an example of the present invention, the slurry may further include a pH adjusting agent, and the pH adjusting agent may include an acidic material or a basic material.

For example, the acidic substance is nitric acid, hydrochloric acid, phosphoric acid, sulfuric acid, hydrofluoric acid, hydrobromic acid, iodic acid, formic acid, malonic acid, maleic acid, oxalic acid, acetic acid, adipic acid, citric acid, adipic acid, acetic acid, propionic acid, It may include at least one selected from the group consisting of fumaric acid, lactic acid, salicylic acid, pimelic acid, benzoic acid, succinic acid, phthalic acid, butyric acid, glutaric acid, glutamic acid, glycolic acid, lactic acid, aspartic acid, tartaric acid, and salts thereof.

For example, the basic material is ammonia, ammonium methyl propanol (AMP), tetra methyl ammonium hydroxide (TMAH), ammonium hydroxide, potassium hydroxide, sodium hydroxide, magnesium hydroxide, hydroxide It may include at least one selected from the group consisting of rubidium, cesium hydroxide, sodium hydrogen carbonate, sodium carbonate and imidazole.

As an example of the present invention, the pH of the polishing slurry composition of the wafer containing polysilicon is 4 to 10; 6 to 10; Or it may have a range of 7 to 9.

If the pH of the polishing slurry composition of the wafer containing polycrystalline silicon is out of the range of 4 to 10, the semiconductor material may be largely eliminated after polishing, and the polishing rate of polycrystalline silicon according to the addition of an amine-based compound containing a benzene group The improvement of the polysilicon film is insignificant, the roughness of the surface of the polysilicon film is not constant, and defects such as dishing, erosion, erosion, corrosion, and surface imbalance may occur. The pH can be adjusted by adding the pH adjusting agent.

As an example of the present invention, the polishing slurry composition for a wafer containing polysilicon may have a polishing rate of 1 Å/min to 3000 Å/min for the polysilicon film; or 5 Å/min to 2500 Å/min; and a polishing rate for an amorphous silicon film of 1 Å/min to 2500 Å/min; or 5 Å/min to 2000 Å/min;

As an example of the present invention, the polishing slurry composition for the wafer containing polysilicon may have a polishing rate of 1 Å/min to 100 Å/min for the silicon oxide film; or 1 Å/min to 30 Å/min;

As an example of the present invention, when a patterned wafer is polished using the polishing slurry composition of a wafer containing polysilicon, a high polishing rate for polysilicon can be secured not only on a wafer having a small pattern density but also on a wafer having a high pattern density. there is.

Hereinafter, the present invention will be described in detail with reference to the following Examples and Comparative Examples. However, the technical spirit of the present invention is not limited or limited thereby.

Example 1 to Example 3

2.0% by weight of colloidal silica abrasive particles having an average particle size of 80 nm in ultrapure water, an organic acid and benzylamine in Table 1, and a pH adjusting agent KOH was added to adjust the pH of the composition to polish a wafer containing polysilicon. A composition was prepared.

comparative example 1 to comparative example 8

A polishing slurry composition for wafers containing polysilicon was prepared in the same manner as in Example 1, except that the organic acids and amines shown in Table 1 were added.

[Polishing conditions]

1. Grinding machine: ST#01 (K.C Tech 300 nm CMP, KC Tech Co., Ltd.)

2. Pad: IC1000 K7 (Dow)

3. Platen RPM: 80

4. Carrier RPM: 83

5. Wafer pressure: 3 psi

6. Retainer Ring Pressure: 7.5 psi

7. Flow rate: 250 ml/min

8. Wafer: TEOS 20,000 Å, Poly Si 5,000 Å, A-Si 2,000 Å deposited blanket wafer

9. Polishing time: 30s

Table 1 below shows the polishing performance according to the colloidal silica, organic acid, amine, and pH added to the polishing slurry composition of the wafers containing the polysilicon of Examples and Comparative Examples.

organic acid amine pH
polishing performance type content
(wt%) type content
(wt%) Poly-Si
(Å) A-Si
(Å) Example 1 glutaric acid 0.3 benzylamine 0.6 8 2157 1212 Example 2 oxalic acid 0.5 benzylamine 0.05 7 248 149 Example 3 oxalic acid 0.5 benzylamine 0.5 7 351 295 Example 4 oxalic acid 0.5 benzylamine 0.5 8 532 421 Comparative Example 1 glutaric acid 0.3 triethanolamine 0.6 8 709 634 Comparative Example 2 glutaric acid 0.3 diethanolamine 0.5 8 576 479 Comparative Example 3 oxalic acid 0.5 triethanolamine 0.05 7 147 82 Comparative Example 4 oxalic acid 0.5 triethanolamine 0.5 7 157 86 Comparative Example 5 oxalic acid 0.5 arginine 0.05 7 152 71 Comparative Example 6 oxalic acid 0.5 formamide 0.05 7 163 89 Comparative Example 7 oxalic acid 0.5 Pyrridine 0.5 7 178 80 Comparative Example 8 oxalic acid 0.5 morpholine 0.5 7 179 75

Referring to Table 1, it can be seen that Examples 1 to 3 including benzyl amine and an organic acid significantly improved the polishing rate of the polysilicon film compared to Comparative Examples 1 to 8 not including benzyl amine. Similarly, it can be confirmed that the polishing rate of the amorphous silicon film also increased. In addition, it can be confirmed that the polishing rate of the polycrystalline silicon film of the slurry composition containing benzyl amine increases as the pH increases.

As described above, although the present invention has been described by the limited embodiments, the present invention is not limited to the above embodiments, and various modifications and variations can be made from these descriptions by those skilled in the art in the field to which the present invention belongs. do. Therefore, the scope of the present invention should not be limited to the described embodiments and should not be defined, and should be defined by not only the claims to be described later, but also those equivalent to these claims.

Claims (12)

abrasive particles;
A polysilicon polishing control agent containing an amine-based compound containing a benzene group; and
polysilicon surface improving agent;
including,
The polysilicon surface improving agent includes an organic acid, an inorganic acid, or both,
The abrasive particles include colloidal silica surface-substituted with a carboxyl group, a sulfone group, or both,
The amine-based compound containing the benzene group includes phenylethylamine, methoxyphenethylamine, aminopropylaniline, bebzylamine, dibenzylamine, and N-methylbenzylamine. (N-Methylbenzylamine), Dimethylbenzylamine, 4-Benzylpiperidine, Dibenzylethanolamine, And at least one selected from the group consisting of tribenzylamine,
Having a pH range of 7 to 10, a polishing slurry composition for a wafer containing polysilicon.
delete According to claim 1,
The polysilicon polishing control agent is 0.0001% by weight to 1% by weight of the polishing slurry composition of the wafer containing polysilicon, the polishing slurry composition of the wafer containing polysilicon.
According to claim 1,
The organic acids include citric acid, malic acid, maleic acid, malonic acid, oxalic acid, succinic acid, lactic acid, tartaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, acetic acid, and adipic acid. , butyric acid, capric acid, caproic acid, caprylic acid, glutaric acid, glycolic acid, formic acid, lauric acid, myristic acid, palmitic acid, phthalic acid, propionic acid, pyruvic acid, stearic acid and valeric acid Including one or more selected species,
The inorganic acid includes at least one selected from the group consisting of sulfuric acid, nitric acid, phosphoric acid, silicic acid, hydrofluoric acid, boric acid, hydrobromic acid, iodic acid, hydrochloric acid and perchloric acid, polishing slurry composition for a wafer containing polysilicon.
According to claim 1,
The polysilicon surface improving agent is 0.001% to 2% by weight of the polysilicon-containing wafer polishing slurry composition, the polishing slurry composition for a wafer containing polysilicon.
According to claim 1,
It further includes; a pH adjusting agent containing an acidic substance or a basic substance;
The acidic substance is nitric acid, hydrochloric acid, phosphoric acid, sulfuric acid, hydrofluoric acid, hydrobromic acid, iodic acid, formic acid, malonic acid, maleic acid, oxalic acid, acetic acid, adipic acid, citric acid, adipic acid, acetic acid, propionic acid, fumaric acid, lactic acid, At least one selected from the group consisting of salicylic acid, pimelic acid, benzoic acid, succinic acid, phthalic acid, butyric acid, glutaric acid, glutamic acid, glycolic acid, lactic acid, aspartic acid, tartaric acid and salts thereof,
The basic material is ammonia, ammonium methyl propanol (AMP), tetramethyl ammonium hydroxide (TMAH), ammonium hydroxide, potassium hydroxide, sodium hydroxide, magnesium hydroxide, rubidium hydroxide, and cesium hydroxide , Sodium hydrogen carbonate, sodium carbonate, imidazole, and a polishing slurry composition for a wafer containing polysilicon, comprising at least one selected from the group consisting of imidazole and salts thereof.
delete delete According to claim 1,
The polishing slurry composition of a wafer containing polycrystalline silicon, wherein the abrasive particles include particles having a single size of 10 nm to 100 nm or mixed particles having two or more different sizes of 10 nm to 100 nm.
According to claim 1,
The abrasive particles are 0.1% to 10% by weight of the polishing slurry composition of the wafer containing polysilicon, the polishing slurry composition of the wafer containing polysilicon.
delete According to claim 1,
The polishing rate for the polycrystalline silicon film is from 1 Å / min to 3000 Å / min, a polishing slurry composition for a wafer containing polysilicon.