TW202142646A - Novel pad-in-a-bottle (pib) technology for advanced chemical-mechanical planarization (cmp) slurries and processes - Google Patents

Abstract

A novel pad-in-a-bottle (PIB) technology for advanced chemical-mechanical planarization (CMP) slurries, systems and processes has been disclosed. The role of conventional polishing pad asperities is played by high-quality micron-size polyurethane (PU) beads that are comparable to the sizes of pores and asperities in polishing pads.

Description

Novel pad-in-bottle (PIB) technology for advanced chemical mechanical planarization (CMP) slurries and methods

Cross-reference of related applications

This case requests the rights of U.S. Provisional Patent Application No. 63/022,737 filed on May 11, 2020. The full text is incorporated herein by reference.

The present invention generally relates to novel pad-in-bottle (PIB) technologies, systems, and methods for advanced chemical mechanical planarization (CMP) slurries. Specifically, the present invention relates to PIB technology, system, and method for ceria-based CMP shallow trench isolation (STI) slurry.

The polishing pad is used in conventional chemical mechanical polishing (CMP). The surface unevenness of the polishing pad plays a key role. The unevenness transmits the normal force and applies tangential motion to the hard nanoscale abrasive particles in the slurry.

The uneven portions on the pads such as polyurethane (PU) pads are irreversibly deformed due to contact with the wafer and are also worn by the slurry particles. Pads with deformed uneven portions usually produce micron-scale scratches on the polished surface. Furthermore, improper control of the shape of the uneven portion of the mat will result in a highly variable contact area distribution, which will result in changes in the removal rate (RR) and wafer-level topography.

Therefore, the surface of the mat must be continuously updated with the emery plate to ensure process stability. In the update procedure, the emery disk will cut the surface of the mat to eliminate the old unevenness and create new unevenness, so the thickness of the mat gradually becomes thinner and replacement (Figure 1).

Therefore, a large amount of waste is generated due to frequent replacement of pads and conditioners in the conventional CMP process.

There are efforts to alleviate the problems caused by the unevenness of the cushion.

The present invention discloses PIB technology, system and method for ceria-based CMP STI slurry developed to meet challenging requirements.

These needs are met by using the disclosed CMP composition, method, and planarization system for oxide-containing substrates.

In one aspect, a CMP polishing composition is provided. The CMP polishing composition includes: Polyurethane (PU) beads; Nano-grade abrasive particles; Dispersant; water; And as needed, pH regulator; Fungicide in The pH of the formulation is 2-12; 4-10 or 5-9.

In another aspect, a CMP polishing method is provided. The CMP polishing method includes: Provide semiconductor substrates with silicon dioxide-containing surfaces; Provide polishing pad; Provide the above chemical mechanical polishing (CMP) formula; Contacting the surface of the semiconductor substrate with the polishing pad and the chemical mechanical polishing formulation; and Polishing the surface of the semiconductor substrate; Wherein, at least a part of the silicon dioxide-containing surface is brought into contact with the polishing pad and the chemical mechanical polishing formula.

In yet another aspect, a CMP polishing system is provided. The CMP polishing system includes: A semiconductor substrate with a surface containing silicon dioxide; Provide polishing pad; Provide the chemical mechanical polishing (CMP) formula of the above-mentioned request; Wherein, at least a part of the silicon dioxide-containing surface is brought into contact with the polishing pad and the chemical mechanical polishing formula.

The present invention discloses a new technology in which high-quality polyurethane (PU) beads with a size ranging from 2 microns to 100 microns, 10 microns to 80 microns, 20 microns to 70 microns or 30 microns to 50 microns play the role of the uneven part of the cushion. Role, the size is equivalent to the size of the pores and uneven parts in commercial polishing pads. Disperse polyurethane beads in an aqueous slurry by means of a surfactant (or wetting agent) as a dispersant, and suspend the beads in polishing with abrasive particles such as calcined ceria, colloidal silica or complex particles In the pulp.

The beads are brought into contact with the wafer surface by the following method to promote polishing in almost the same way as the conventional uneven portion (Figure 1).

By selecting the size of the bead and its concentration in the slurry, the height, curvature and areal density of the "peak" in contact with the wafer can be better controlled, thereby substantially reducing the contact with the conventional unevenness The process variability.

The application of beads still requires the second surface or the opposite surface to be polished. In our case, the second surface continues to use the conventional polyurethane-based pad, but since it is no longer the main surface for polishing, it requires minimal conditioning. Or, as shown in Figure 2, an inexpensive and partially conditioned cushion can be used as the opposite surface.

Commercial polishing machines can use 2 to 3 polishing pads and conditioners at the same time. Generally, the service life of the mat and conditioning plate is reached after two consecutive days of use. Therefore, each platen in the CMP equipment has to use hundreds of pads and conditioners every year, and since the wafer fabrication facility can have dozens of equipment (2 or 3 platens on each equipment), The total cost of mats and mat conditioners alone is very considerable.

Since it may take several hours to remove the old mats, install the new mats and then carry out the quality evaluation, the engineering and product losses caused by the equipment shutdown and the consumables used to evaluate the quality of the new mats are very large. The used PU pad and the discarded emery disk conditioner represent the waste of the CMP process.

In the case of the mat, only about two-thirds of the total thickness of the mat is used before the mat must be peeled off and discarded. Regarding the conditioner, only a few hundred pieces of emery in the tens of thousands of emery control the service life of the product, and the conditioner must be discarded afterwards. Furthermore, recycling or reuse options are not applicable to mats and conditioners. This waste can also cause environmental, health and safety (EHS) issues. The present invention solves the above-mentioned EHS problem, and provides a novel solution for the current standard CMP process by reducing and ultimately eliminating the use of conventional polishing pads and emery disk conditioners.

Several specific aspects of the present invention are summarized below. Aspect 1: A CMP polishing composition comprising: Polyurethane (PU) beads; Abrasive particles Dispersant; water; And as needed, pH regulator; Fungicide in The pH of the formulation is 2-12; 4-10 or 5-9. Aspect 2: A CMP polishing method, which includes: Provide semiconductor substrates with silicon dioxide-containing surfaces; Provide polishing pad; Provide the above chemical mechanical polishing (CMP) formula; Contacting the surface of the semiconductor substrate with the polishing pad and the chemical mechanical polishing formulation; and Polishing the surface of the semiconductor substrate; Wherein, at least a part of the silicon dioxide-containing surface is brought into contact with the polishing pad and the chemical mechanical polishing formula. Aspect 3: A CMP polishing system, which includes: A semiconductor substrate with a surface containing silicon dioxide; Provide polishing pad; Provide the above chemical mechanical polishing (CMP) formula; Wherein, at least a part of the silicon dioxide-containing surface is brought into contact with the polishing pad and the chemical mechanical polishing formula.

The polyurethane (PU) beads have a micron size ranging from 2 microns to 100 microns, from 10 microns to 80 microns, from 20 microns to 70 microns, or from 30 microns to 50 microns.

The concentration of the polyurethane (PU) beads may be between about 0.010% by weight to about 5.0% by weight, about 0.025% by weight to about 2.5% by weight, about 0.05% by weight to about 1.0% by weight, or 0.10% by weight to about 0.50% by weight . The weight percentage is relative to the composition.

The abrasive particles include, but are not limited to, inorganic oxide particles, metal oxide-coated inorganic oxide particles, metal oxide-coated organic polymer particles, and combinations thereof.

The inorganic oxide particles include, but are not limited to, ceria, colloidal silica, high-purity colloidal silica, fuming silica, colloidal ceria, alumina, titania, and zirconia particles.

The metal oxide-coated inorganic oxide particles include, but are not limited to, ceria-coated inorganic oxide particles, such as ceria-coated colloidal silica, and ceria-coated high-purity colloidal silica. Silica, ceria-coated alumina, ceria-coated titania, ceria-coated zirconia, or any other ceria-coated inorganic oxide particles.

The metal oxide-coated organic polymer particles are selected from the group consisting of ceria-coated organic polymer particles and zirconia-coated organic polymer particles.

The abrasive particles have an average particle size (MPS) of 20 nm to 500 nm, 50 nm to 400 nm, 100 nm to 350 nm, or 180 nm to 220 nm. MPS can be measured by dynamic light scattering (DLS) method.

The concentration of the abrasive may range from about 0.01% by weight to about 30% by weight, preferably from about 0.05% by weight to about 10% by weight, more preferably from about 0.1% by weight to about 2% by weight. The weight percentage is relative to the composition.

The dispersant is any agent that can disperse polyurethane beads in an aqueous solution.

(1)， 其中 a介於1至50、1至40、1至30、1至20、1至10或1至5； b、c及a’可為相同或不同，並且各自獨立地介於0至50、0至40、0至30、0至20、0至10或0至5； n及m可為相同或不同，並且各自獨立地介於0至12、0至8、1至5或2至4； 側鏈R及R’基團可為相同或不同，並且各自獨立地選自由以下所組成的群組： 氫； –(CH₂ )_p CH₃ 烷基，並且p介於1至12或2至5，較佳為2至5； -NH₂ 基團； -NH(CH₂ )_q -NH₂ 基團，並且q 介於1至12或2至5，較佳的； 環氧乙烷(EO)及環氧丙烷(PO)重複基團：-(EO)e-(PO)d-OH，並且d及e各自獨立地介於1至50、1至40、1至30、1至20、1至10或1至5，較佳為1至10，更佳為1至5； -COOH； R¹ COOH，並且R¹ 為–(CH₂ )_m ，並且m 介於1至12； R¹ SO₃ H； –(C₆ H₄ )_n ，並且n 介於1至4； -COOM，並且m為Na⁺ 、K⁺ 或NH4⁺ ，較佳為K⁺ 或NH4⁺ ； -R¹ COOM； -COOR² ，並且R² 為–(CH₂ )_m H、–(CH₂ )_m COOH (m = 1至12)或–(CH₂ )_m COOM (M = Na⁺ 、K⁺ 或NH4⁺ ，較佳為K⁺ 或NH4⁺ )，較佳為–(CH₂ )_m H或–(CH₂ )_m COOH (m = 1至12)； -R¹ COOR² ； SO₃ H； -SO₃ M； 膦酸； 選自鈉鹽、鉀鹽或銨鹽的磷酸鹽； 選自鈉苯甲基、二苯甲基或其他芳族部分的芳族基團。Examples of dispersants have the following general molecular structure (1):

(1), where a is between 1 to 50, 1 to 40, 1 to 30, 1 to 20, 1 to 10, or 1 to 5; b, c and a'may be the same or different, and each independently lies between 0 to 50, 0 to 40, 0 to 30, 0 to 20, 0 to 10, or 0 to 5; n and m may be the same or different, and each independently ranges from 0 to 12, 0 to 8, 1 to 5 Or 2 to 4; The side chain R and R'groups can be the same or different, and are each independently selected from the group consisting of: hydrogen; -(CH ₂ ) _p CH ₃ alkyl, and p is between 1 To 12 or 2 to 5, preferably 2 to 5; -NH ₂ group; -NH(CH ₂ ) _q -NH ₂ group, and q is between 1 to 12 or 2 to 5, preferably; ring Ethylene oxide (EO) and propylene oxide (PO) repeating groups: -(EO)e-(PO)d-OH, and d and e are each independently between 1 to 50, 1 to 40, and 1 to 30 , 1 to 20, 1 to 10, or 1 to 5, preferably 1 to 10, more preferably 1 to 5; -COOH; R ¹ COOH, and R ¹ is -(CH ₂ ) _m , and m is between 1 To 12; R ¹ SO ₃ H; -(C ₆ H ₄ ) _n , and n is between 1 to 4; -COOM, and m is Na ⁺ , K ⁺ or NH4 ⁺ , preferably K ⁺ or NH4 ⁺ ; -R ¹ COOM; -COOR ² , and R ² is -(CH ₂ ) _m H, -(CH ₂ ) _m COOH (m = 1 to 12) or -(CH ₂ ) _m COOM (M = Na ⁺ , K ⁺ Or NH4 ⁺ , preferably K ⁺ or NH4 ⁺ ), preferably -(CH ₂ ) _m H or -(CH ₂ ) _m COOH (m = 1 to 12); -R ¹ COOR ² ; SO ₃ H ; -SO ₃ M; Phosphonic acid; Phosphates selected from sodium, potassium or ammonium salts; Aromatic groups selected from sodium benzyl, benzhydryl or other aromatic moieties.

Examples are silsulf E608, silquat DI-25 PG, silsulf J208-6, silsulf A008-AC-UP, silplex J2-S, provided by SILTECH at 225 Wicksteed Avenue, M4H 1G5, Toronto, Ontario, Canada. silquat CR4000, silquat D2, silsulf CR1115 and silsulf A208.

Silsulf dispersant is a silicon-containing polyether molecule with EO-PO repeating side chain functional groups. Preferably, it is a Silsulf type dispersant.

The concentration of the dispersant is between about 0.0025% by weight to about 5.0% by weight, about 0.01% by weight to about 2.5% by weight, 0.025% by weight to about 1.0% by weight, or 0.050% by weight to about 0.5% by weight.

The pH of the CMP composition is about 2-12; 4-10 or 5-9.

The pH of the composition can be adjusted with a suitable pH adjusting agent, such as a suitable acid, base, amine, or any combination thereof. Preferably, the pH adjusting agent used in the composition does not contain metal ions, so that undesirable metal components are not introduced into the composition. Suitable pH adjusting agents include amines, ammonium hydroxide, nitric acid, phosphoric acid, sulfuric acid, organic acids and/or their salts and any combination thereof.

The composition may contain 0 weight percent to 1 weight percent, preferably 0.005 weight percent to 0.5 weight percent, more preferably 0.02 weight percent to 0.2 weight percent of a pH adjuster, the pH adjuster is used to select acidic pH conditions Free from the group consisting of nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid, other inorganic or organic acids and their mixtures, or used for alkaline pH conditions selected from sodium hydride, potassium hydroxide, ammonium hydroxide, tetraoxane hydroxide Base ammonium, organic quaternary ammonium hydroxide, organic amine, and combinations thereof.

The CMP composition may contain biological growth inhibitors or preservatives to prevent the growth of bacteria and fungi during storage.

The biological growth inhibitor includes, but is not limited to, tetramethylammonium chloride, tetraethylammonium chloride, tetrapropylammonium chloride, alkylbenzyldimethylammonium chloride, and alkylbenzyl hydroxide Dimethylammonium (wherein the alkyl chain is between 1 and about 20 carbon atoms), sodium chlorite and sodium hypochlorite.

Some commercially available preservatives include the KATHON™ and NEOLENE™ product lines from Dow Chemicals and the Preventol™ line from Lanxess. U.S. Patent No. 5,230,833 (Romberger et al.) and U.S. Patent Application US 20020025762 disclose more. Its content is hereby incorporated in its entirety by reference.

The use of a biocide in a sealed CMP polishing composition can reduce or eliminate bacteria and other microorganisms, especially when the pH of the CMP polishing composition is close to or near neutral pH conditions. The bactericide ranges from about 0.0001% to about 0.03% by weight of the CMP composition. Working example

It has been shown to use 15 micron or 35 micron PU beads, wetting agent, running-in IC-1070 pad, and commercially available calcined ceria-based STI 2100F series (Versum Materials) slurry containing nano-level abrasive particles. For example, the average RR of silicon dioxide on the blank wafer and the wafer-to-wafer equivalent to the existing step height (step height), the shallow disk effect and the erosion result on the patterned STI wafer, which resulted in a significant improvement RR stability.

It has been shown that the PIB technology can also significantly reduce the lateral vibration of the wafer during polishing.

The following non-limiting examples are presented to further illustrate the present invention. CMP methodology

In the examples presented below, CMP experiments were performed using the procedures and experimental conditions specified below. Glossary Component

The chemical additive, Silsulf E608, was provided by SILTECH Company, 225 Wicksteed Avenue, M4H 1G5, Toronto, Ontario, Canada.

Dainichiseika Color & Chemicals Manufacturing Co., Ltd. Akabane & Sakura production plant at 1-4-3, Uma, Kita-ku, Tokyo, provides 15-micron and 35-micron polyurethane beads.

TEOS: Tetraethyl orthosilicate

Polishing pads: polishing pads, IC1070 and other pads, used during CMP, provided by DOW-Dupont Co., Ltd. parameter General rule

Å or A: Angstrom-unit of length

BP: back pressure, in psi

CMP: Chemical Mechanical Planarization = Chemical Mechanical Polishing

CS: Vehicle speed

DF: Down force: the pressure applied during CMP, in psi

min: minutes

ml: milliliters

mV: millivolt

psi: pounds per square inch

PS: The rotation speed of the pressure plate of the polishing equipment, in rpm (revolutions per minute)

SF: Pulp flow rate, ml/min

Weight %: (of listed components) weight percentage

TEOS removal rate: TEOS removal rate measured under specified down pressure. In the listed examples, the down pressure of the CMP equipment is set to different psi. Metrology

The film was measured with a ResMap CDE model 168 manufactured by Creative Design Engineering, Alves Dr. 20565, Cupertino, California, 95014. The ResMap device is a four-point probe sheet resistance device. A forty-nine-point diameter scan of the film was performed at the 5 mm edge exclusion. CMP equipment

The CMP equipment used was a 200mm Mirra manufactured by Applied Materials, Inc., 3050 Bowers Avenue, Santa Clara, California, 95054. The platen 1 for blank and patterned wafer research was used with IC 1070 pads supplied by DOW-Dupont, 451 Bellevue Road, Newark, Delaware.

The IC1070 pad or other pad is broken in by conditioning the pad on the conditioner for 18 minutes under 7 pounds of downforce. In order to verify the equipment settings and the pad running-in, the Versum® STI2305 slurry supplied by Versum Materials Co., Ltd. was used to polish two tungsten monitors and two TEOS monitors under benchmark conditions. Wafer

Use PECVD TEOS wafers for polishing experiments. These blank wafers were purchased by Silicon Valley Microelectronics, 2985 Kifer Road, Santa Clara, California, 95051. Polishing experiment

In the blank wafer study, the oxide blank wafer was polished with a slurry flow rate of 200 ml/min under reference conditions.

The slurry was used for polishing experiments on patterned wafers (MIT860) supplied by SWK Associates, Inc. 2920 Scott Avenue, 95054, Santa Clara, California. These wafers are measured on a Veeco VX300 profiler/AFM instrument. The three pitch structures of different sizes are used for oxide shallow disk effect measurement. The wafer is measured at the center, middle and edge die positions.

In all working examples, the reference sample uses 0.5% by weight average particle size (MPS) (measured by dynamic light scattering (DLS)) of calcined ceria with a range of 180 nm to 220 nm as the abrasive, 0.077% by weight Polyacrylate is used as a chemical additive, and 0.0002% by weight Kathon II is used as a bactericide. Adjust the pH to 5.15. Example 1

Use 0.5% by weight of calcined cerium oxide as an abrasive, 0.077% by weight of polyacrylate as a chemical additive, 0.0002% by weight of Kathon II as a bactericide, and 0.05% of Silsurf E608 (silicon-containing polyether compound) as a dispersion The agent was made into test sample one. Adjust the pH to 5.15.

Use 0.5% by weight of calcined cerium oxide as an abrasive, 0.077% by weight of polyacrylate as a chemical additive, 0.0002% by weight of Kathon II as a bactericide, and 0.05% of Silsurf E608 (silicon-containing polyether compound) as a dispersion And 0.25% by weight of 15 micron polyurethane beads to make test sample two (PIB sample). Adjust the pH to 5.15.

Use 0.5% by weight of calcined cerium oxide as an abrasive, 0.077% by weight of polyacrylate as a chemical additive, 0.0002% by weight of Kathon II as a bactericide, and 0.05% of Silsurf E608 (silicon-containing polyether compound) as a dispersion And 0.25% by weight of 35-micron polyurethane beads to make test sample three (PIB sample). Adjust the pH to 5.15. Table 1. TEOS removal rate (A/min.) comparison sample TEOS RR (Å/min.) Reference sample 1214 Reference sample + Silsulf E608 1067 Reference sample + Silsulf E608 + 15 micron PU beads 1143 Reference sample + Silsulf E608 + 35 micron PU beads 1050

Use 200 mm Mirra polishing machine (from AMAT company), DowDupont IP1070 polishing pad and Saesol emery conditioning disk for polishing test. The applied slurry flow rate was 200 mL/min. Polish the TEOS blank wafer. The polishing results are listed in Table 1.

As shown in the results of TEOS removal rate shown in Table 1, after adding the dispersant Silsulf E608 to the reference sample under the same pH conditions, the dispersant's passivation effect on the surface of the oxide film reduces the removal rate of the TEOS Up. 15 micron and 35 micron polyurethane beads were used to obtain similar TEOS membrane removal rates from this sample. Example 2

Use 0.5% by weight of calcined cerium oxide as an abrasive, 0.077% by weight of polyacrylate as a chemical additive, 0.0002% by weight of Kathon II as a bactericide, and 0.05% of Silsurf E608 (silicon-containing polyether compound) as a dispersion And 0.25% by weight of 35-micron polyurethane beads (so-called PU beads) to make a test sample (PIB sample). Adjust the pH to 5.15.

Both the reference sample and the test sample were used to polish the oxide patterned wafer. The effect of the PIB-type oxide polishing composition and the reference sample on the remaining SiN thickness was compared and the results are listed in Table 2. Table 2. The influence of PIB-type STI slurry on the remaining SiN thickness The remaining SiN film thickness (Å) sample 30% density (Å) 50% density (Å) 70% density (Å) 90% density (Å) Reference sample 1155 1380 1225 1335 Reference sample + Silsulf E608 + 35 micron PU beads 1415 1371 1234 1226

As shown in Table 2, the PIB-type STI slurry samples provide a larger remaining SiN film thickness on the 30% density feature, and provide a similar remaining SiN film thickness on the 50% and 70% density features. It is preferable to leave a larger SiN film thickness when polishing the oxide patterned wafer. Example 3

Use 0.5% by weight of calcined ceria as abrasive, 0.077% by weight of polyacrylate as chemical additives, 0.0002% by weight of Kathon II as bactericide, and 0.05% by weight of Silsurf E608 as dispersant to prepare test sample one. Adjust the pH to 5.15.

Use 0.5% by weight of calcined cerium oxide as an abrasive, 0.077% by weight of polyacrylate as a chemical additive, 0.0002% by weight of Kathon II as a bactericide, and 0.05% of Silsurf E608 (silicon-containing polyether compound) as a dispersion And 0.25% by weight of 35-micron polyurethane beads (PU beads) to make test sample two (PIB sample). Adjust the pH to 5.15.

The two test samples were used to polish oxide patterned wafers, and the effects of PIB-type oxide polishing composition and non-PIB samples on the remaining SiN thickness were compared and the results are listed in Table 3. Table 3. The influence of PIB-type STI slurry on the remaining SiN thickness The remaining SiN film thickness (Å) sample 30% density (Å) 50% density (Å) 70% density (Å) 90% density (Å) Reference sample + Silsulf E608 903 924 878 870 Reference sample + Silsulf E608 + 35 micron PU beads 1169 1151 1075 1108

As shown in Table 3, the PIB-type STI slurry sample provides a larger residual SiN film thickness than the non-PIB sample in all four-density characteristics, and the two samples use the same weight% dispersant and the same pH conditions. . It is preferable to leave a larger SiN film thickness when polishing the oxide patterned wafer. Example 4

In Example 4, 0.5% by weight of calcined ceria was used as the abrasive, 0.077% by weight of polyacrylate as the chemical additive, 0.0002% by weight of Kathon II as the bactericide, and 0.05% by weight of Silsurf E608 as the dispersant. Make test sample one. Adjust the pH to 5.15.

Use 0.5% by weight of calcined cerium oxide as an abrasive, 0.077% by weight of polyacrylate as a chemical additive, 0.0002% by weight of Kathon II as a bactericide, and 0.05% of Silsurf E608 (silicon-containing polyether compound) as a dispersion And 0.25% by weight of 35-micron polyurethane beads to make test sample two (PIB sample). Adjust the pH to 5.15.

The two test samples were both used to polish oxide patterned wafers. The PIB-type oxide polishing composition and non-PIB samples were used to compare the remaining SiN thickness on all features of 100 microns, 200 microns, and 500 microns at a density of 50%. Impact and the results are listed in Table 4. Table 4. The influence of PIB-type STI slurry on the remaining SiN thickness Remaining SiN film thickness on 50% density feature (Å) sample 100 µm 200 µm 500 µm Reference sample + Silsulf E608 991 914 886 Reference sample + Silsulf E608 + 35 micron PU beads 1386 1389 1188

As shown in Table 4, the PIB-type STI slurry sample provides a larger residual SiN film thickness on the features of 50% density of 100 microns, 200 microns, and 500 microns than the non-PIB sample, and the two samples use the same weight. % Dispersant and the same pH conditions. It is preferable to leave a larger SiN film thickness when polishing the oxide patterned wafer. Example 5

Use 0.5% by weight of calcined cerium oxide as an abrasive, 0.077% by weight of polyacrylate as a chemical additive, 0.0002% by weight of Kathon II as a bactericide, and 0.05% by weight of Silsurf E608 (silicon-containing polyether compound) as Dispersant and 0.25% by weight of 35-micron polyurethane beads were made into test samples (PIB samples). Adjust the pH to 5.15.

Both the reference sample and the test sample are used to polish oxide patterned wafers. The effect of the PIB-type oxide polishing composition and the reference sample on the shallow disc effect of oxide trenches on 4 different density features are compared and the results are listed in the table 5. Table 5. The influence of PIB-type STI slurry on the shallow disk effect (Å) of the oxide trench Oxide trench shallow disk effect (Å) sample 30% density (Å) 50% density (Å) 70% density (Å) 90% density (Å) Reference sample 49 57 91 107 Reference sample + Silsulf E608 + 35 micron PU beads 39 36 58 47

As shown in Table 5, the PIB-type STI slurry sample provides a lower oxide trench shallow disk effect than the non-PIB reference sample without the dispersant in all four test density characteristics. It is preferable to have a lower oxide trench shallow dish effect when polishing oxide patterned wafers. Example 6

In Example 6, 0.5% by weight of calcined ceria was used as the abrasive, 0.077% by weight of polyacrylate as the chemical additive, 0.0002% by weight of Kathon II as the bactericide, and 0.05% by weight of Silsurf E608 as the dispersant. Make test sample one. Adjust the pH to 5.15.

Use 0.5% by weight of calcined cerium oxide as an abrasive, 0.077% by weight of polyacrylate as a chemical additive, 0.0002% by weight of Kathon II as a bactericide, and 0.05% of Silsurf E608 (silicon-containing polyether compound) as a dispersion And 0.25% by weight of 35-micron polyurethane beads to make test sample two (PIB sample). Adjust the pH to 5.15.

The two test samples were used to polish oxide patterned wafers. The effects of the PIB-type oxide polishing composition and the non-PIB sample on the oxide trench shallow disk effect were compared and the results are listed in Table 6. Table 6. The influence of PIB-type STI slurry on the shallow disc effect (Å) of oxide trenches Oxide trench shallow disk effect (Å) sample 30% density (Å) 50% density (Å) 70% density (Å) 90% density (Å) Reference sample + Silsulf E608 39 54 77 62 Reference sample + Silsulf E608 + 35 micron PU beads 27 twenty one 15 1

As shown in Table 6, when the two samples use the same weight% of dispersant and under the same pH conditions, the PIB-type STI pulp sample provides lower than the non-PIB reference sample in all four density characteristics. The oxide trench shallow disk effect. It is preferable to have a lower and reduced shallow dish effect of oxide trenches when polishing oxide patterned wafers. Example 7

In Example 7, 0.5% by weight of calcined ceria was used as the abrasive, 0.077% by weight of polyacrylate as the chemical additive, 0.0002% by weight of Kathon II as the bactericide, and 0.05% by weight of Silsurf E608 as the dispersant. Make test sample one. Adjust the pH to 5.15.

Use 0.5% by weight of calcined cerium oxide as an abrasive, 0.077% by weight of polyacrylate as a chemical additive, 0.0002% by weight of Kathon II as a bactericide, and 0.05% of Silsurf E608 (silicon-containing polyether compound) as a dispersion And 0.25% by weight of 35-micron polyurethane beads to make test sample two (PIB sample). Adjust the pH to 5.15.

The two test samples are both used to polish oxide patterned wafers. Compare PIB-type oxide polishing composition and non-PIB samples to all oxide trenches on 100 micron, 200 micron and 500 micron features at 50% density. The impact of the shallow pan effect and the results are listed in Table 7. Table 7. The influence of PIB-type STI slurry on the shallow disc effect (Å) of oxide trenches Oxide trench shallow disk effect (Å) sample 100 µm 200 µm 500 µm Reference sample + Silsulf E608 38 107 142 Reference sample + Silsulf E608 + 35 micron PU beads 25 36 75

As shown in Table 7, when the two samples use the same weight% of dispersant and under the same pH conditions, the PIB type STI slurry sample provides a ratio of 50% density on 100 micron, 200 micron and 500 micron features. The non-PIB reference sample has lower oxide trench shallow disc effect. It is preferable to have a lower and reduced shallow dish effect of oxide trenches when polishing oxide patterned wafers.

The specific examples of the present invention listed above, including working examples, are examples of numerous specific examples that can be constituted by the present invention. It is expected that many other configurations of the method can be used, and the materials used in the method can be selected from many materials other than those specifically disclosed.

130: Polyurethane beads 146: Polyurethane pad

Figure 1 (previous art) shows a conventional CMP polishing using a polyurethane pad 146.

Figure 2 shows PIB CMP polishing using polyurethane pad 146 and polyurethane beads (130).

130: Polyurethane beads

146: Polyurethane pad

Claims (16)

A chemical mechanical polishing (CMP) formulation, which contains: Polyurethane (PU) beads; Abrasive particles Dispersant, and water; in The pH of the formulation is 2-12, 4-10, or 5-9. Such as the chemical mechanical polishing (CMP) formulation of claim 1, wherein the polyurethane (PU) beads have a micron size ranging from 2 microns to 100 microns, 10 microns to 80 microns, 20 microns to 70 microns, or 30 microns to 50 microns . Such as the chemical mechanical polishing (CMP) formulation of claim 1, wherein the concentration of polyurethane (PU) beads is between 0.01% by weight to 5.0% by weight, 0.025% by weight to 2.5% by weight, 0.05% by weight to 1.0% by weight or 0.10% by weight % To 0.50% by weight. The chemical mechanical polishing (CMP) formulation of claim 1, wherein the abrasive particles are selected from the group consisting of inorganic oxide particles, metal oxide-coated inorganic oxide particles, metal oxide-coated organic polymer particles, and combinations thereof Groups formed. Such as the chemical mechanical polishing (CMP) formulation of claim 1, wherein the abrasive particles are inorganic oxide particles selected from the group consisting of ceria, silica, colloidal silica, fuming dioxide Silicon, colloidal ceria, alumina, titania, zirconia particles and combinations thereof. The chemical mechanical polishing (CMP) formulation of claim 1, wherein the abrasive particles are metal oxide-coated inorganic oxide particles selected from the group consisting of: ceria-coated colloidal silica, Ceria-coated alumina, ceria-coated titania, ceria-coated zirconia, and combinations thereof. The chemical mechanical polishing (CMP) formulation of claim 1, wherein the abrasive particles are selected from the group consisting of ceria-coated organic polymer particles, zirconia-coated organic polymers, and combinations thereof. Metal oxide organic polymer particles. Such as the chemical mechanical polishing (CMP) formulation of claim 1, wherein the abrasive particles have an average particle size (MPS) of 20 nm to 500 nm, 50 nm to 400 nm, 100 nm to 350 nm, or 180 nm to 220 nm. Such as the chemical mechanical polishing (CMP) formulation of claim 1, wherein the concentration of abrasive particles is between 0.01% by weight and 30% by weight, between 0.05% by weight and 10% by weight, or between 0.1 and 2% by weight. Such as the chemical mechanical polishing (CMP) formulation of claim 1, wherein the dispersant has the following general molecular structure (1):

(1), where a is between 1 to 50, 1 to 40, 1 to 30, 1 to 20, 1 to 10, or 1 to 5; b, c and a'may be the same or different, and each independently lies between 0 to 50, 0 to 40, 0 to 30, 0 to 20, 0 to 10, or 0 to 5; n and m may be the same or different, and each independently ranges from 0 to 12, 0 to 8, 1 to 5 Or 2 to 4; The side chain R and R'groups can be the same or different, and are each independently selected from the group consisting of: hydrogen; -(CH ₂ ) _p CH ₃ alkyl, and p is between 1 To 12 or 2 to 5, preferably 2 to 5; -NH ₂ group; -NH(CH ₂ ) _q -NH ₂ group, and q is between 1 to 12 or 2 to 5, preferably; ring Ethylene oxide (EO) and propylene oxide (PO) repeating groups: -(EO)e-(PO)d-OH, and d and e are each independently between 1 to 50, 1 to 40, and 1 to 30 , 1 to 20, 1 to 10, or 1 to 5, preferably 1 to 10, more preferably 1 to 5; -COOH; R ¹ COOH, and R ¹ is -(CH ₂ ) _m , and m is between 1 To 12; R ¹ SO ₃ H; -(C ₆ H ₄ ) _n , and n is between 1 to 4; -COOM, and m is Na ⁺ , K ⁺ or NH4 ⁺ , preferably K ⁺ or NH4 ⁺ ; -R ¹ COOM; -COOR ² , and R ² is -(CH ₂ ) _m H, -(CH ₂ ) _m COOH (m = 1 to 12) or -(CH ₂ ) _m COOM (M = Na ⁺ , K ⁺ Or NH4 ⁺ , preferably K ⁺ or NH4 ⁺ ), preferably -(CH ₂ ) _m H or -(CH ₂ ) _m COOH (m = 1 to 12); -R ¹ COOR ² ; SO ₃ H ; -SO ₃ M; Phosphonic acid; Phosphates selected from sodium, potassium or ammonium salts; Aromatic groups selected from sodium benzyl, benzhydryl or other aromatic moieties. Such as the chemical mechanical polishing (CMP) formulation of claim 10, wherein the side chain R and R'groups are the same or different ethylene oxide (EO) and propylene oxide (PO) repeating groups: -(EO) e-(PO)d-OH, and d and e are each independently between 1 and 10, and b and c cannot be all 0. Such as the chemical mechanical polishing (CMP) formulation of claim 10, wherein the side chain R and R'groups are the same or different ethylene oxide (EO) and propylene oxide (PO) repeating groups: -(EO) e-(PO)d-OH, and d and e are each independently between 1 and 5, and b and c cannot be all 0. Such as the chemical mechanical polishing (CMP) formulation of claim 1, wherein the concentration of the dispersant is between 0.0025% by weight to 5.0% by weight, 0.01% by weight to 2.5% by weight, 0.025% by weight to 1.0% by weight, or 0.050% by weight to 0.50 weight%. Such as the chemical mechanical polishing (CMP) formula of claim 1, wherein the chemical mechanical polishing (CMP) formula additionally includes at least one of the following: pH adjusters, which are selected from the group consisting of amines, ammonium hydroxide, nitric acid, phosphoric acid, sulfuric acid, organic acids and/or their salts and any combination thereof; and Bactericide, which is selected from tetramethylammonium chloride, tetraethylammonium chloride, tetrapropylammonium chloride, alkylbenzyldimethylammonium chloride, alkylbenzyldimethylammonium chloride Ammonium (which has an alkyl chain between 1 to about 20 carbon atoms), sodium chlorite and sodium hypochlorite, and combinations thereof. A method for chemical mechanical polishing of a semiconductor substrate, which comprises the following steps: Provide semiconductor substrates with silicon dioxide-containing surfaces; Provide polishing pad; Provide the chemical mechanical polishing (CMP) formula of any one of request items 1 to 14; Contacting the surface of the semiconductor substrate with the polishing pad and the chemical mechanical polishing formulation; and Polishing the surface of the semiconductor substrate; Wherein, at least a part of the silicon dioxide-containing surface is brought into contact with the polishing pad and the chemical mechanical polishing formula. A chemical mechanical polishing system, which includes: A semiconductor substrate with a surface containing silicon dioxide; Provide polishing pad; Provide the chemical mechanical polishing (CMP) formula of any one of request items 1 to 14.

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