CN120752317A

CN120752317A - Chemical Mechanical Planarization for Shallow Trench Isolation

Info

Publication number: CN120752317A
Application number: CN202480012548.XA
Authority: CN
Inventors: J·D·罗斯; K·P·穆瑞拉; 周鸿君; 甘露; 史晓波
Original assignee: Versum Materials US LLC
Current assignee: Versum Materials US LLC
Priority date: 2023-02-17
Filing date: 2024-01-30
Publication date: 2025-10-03
Also published as: JP2026506673A; KR20250150100A; TW202507842A; WO2024173029A1; EP4665809A1

Abstract

The present invention provides chemical mechanical planarization polishing (CMP) compositions for Shallow Trench Isolation (STI) applications. The CMP composition contains ceria coated inorganic oxide particles as abrasive, such as ceria coated silica particles or any other ceria coated inorganic oxide particles as core particles, a nonionic organic alcohol compound having at least two hydroxyl groups on the same molecule, a chemical additive having at least one or at least two carboxyl functional groups and at least two hydroxyl groups on the same molecule. And optionally a biocide and a pH adjuster, for use in the STI polishing composition, wherein the pH of the composition is from 2 to 12, preferably from 3 to 11, more preferably from 4 to 10, and most preferably from 5 to 9. The disclosed STI polishing composition provides low erosion on various density features of the polished STI patterned wafer.

Description

Chemical mechanical planarization for shallow trench isolation

Cross Reference to Related Applications

The present application claims the benefit of U.S. provisional patent application No.63/485,671 filed on day 17, 2, 2023, which is incorporated herein by reference as if fully set forth.

Background

The present invention relates to a STICMP chemical polishing composition and Chemical Mechanical Planarization (CMP) for Shallow Trench Isolation (STI) processes.

An important step involved in the fabrication of microelectronic devices is polishing, particularly surfaces used for chemical mechanical polishing for the purpose of recycling selected materials and/or planarizing structures.

For example, a SiN layer is deposited under the SiO ₂ layer to act as a polish stop layer. The role of such a polish stop layer is particularly important in Shallow Trench Isolation (STI) structures. Selectivity is characterized by the ratio of oxide polishing rate to nitride polishing rate. An example is an increased polishing selectivity ratio of silicon dioxide (SiO ₂) compared to silicon nitride (SiN).

In global planarization of patterned STI structures, reducing erosion on various density features of polished STI patterned wafers is a critical factor to consider. The lower erosion on the various density features of the polished STI patterned wafer will prevent current leakage between adjacent transistors. Non-uniform trench oxide loss across the die (intra-die) affects transistor performance and device manufacturing yield. Severe erosion on the various density features of the polished STI patterned wafer causes poor isolation of the transistor, resulting in device failure. It is therefore important to reduce erosion on the various density features of the polished STI patterned wafer.

As semiconductor manufacturers move to more advanced node chip fabrication, further reduction in SiN film removal rates, improvement in SiO ₂ SiN selectivity, and reduction in erosion on the various density features of polished STI patterned wafers become more important to increase chip fabrication yield.

Published U.S. patent application 2020/0048551A1 discloses polishing compositions comprising ceria coated silica particles and an organic acid having one selected from the group consisting of sulfonic acid groups, phosphonic acid groups, pyridine compounds, and combinations thereof, having a pH of 5 to 10 and an electrical conductivity of 0.2 to 10 millisiemens/cm, providing very high silica removal rates for advanced semiconductor device fabrication.

Published U.S. patent application 2020/0071566A1 discloses a slurry composition for a Chemical Mechanical Polishing (CMP) process comprising about 0.1 to about 10 wt.% of polishing particles, about 0.001 to about 1 wt.% of an amine compound, about 0.001 to about 1 wt.% of a first cationic compound which is an amino acid, about 0.001 to about 1 wt.% of a second cationic compound which is an organic acid, and about 1 to about 5 wt.% of a polyol comprising at least two hydroxyl groups.

Published U.S. patent application 2021/013681A 1 discloses Chemical Mechanical Polishing (CMP) slurry compositions, such as CMP slurry compositions for polishing Indium Tin Oxide (ITO) layers, and methods of making semiconductor devices using such CMP slurry compositions. The CMP slurry composition can include polishing particles, a dispersant, a supplemental oxidizing agent, and a sugar alcohol compound.

Published U.S. patent applications 2020/0002607A1 and 2020/0002608A1 disclose Chemical Mechanical Planarization (CMP) polishing compositions, methods, and systems that provide for reducing oxide trench dishing and improving overpolish window stability. High and tunable silicon oxide removal rates, low silicon nitride removal rates, and tunable SiO ₂ to SiN selectivities are also provided. The composition uses an abrasive such as ceria coated silica particles, and a unique combination of chemical additives such as maltitol, lactitol, maltotriose alcohol, ribitol, D-sorbitol, mannitol, dulcitol, iditol, D- (-) -fructose, sorbitan, sucrose, ribose, inositol, glucose, D-arabinose, L-arabinose, D-mannose, L-mannose, meso-erythritol, beta-lactose, arabinose, or a combination thereof as oxide trench dishing reducing additives.

However, those previously disclosed Shallow Trench Isolation (STI) polishing compositions do not address the importance of reducing feature erosion of various sizes and high oxide to nitride selectivity on polished patterned wafers.

From the foregoing, it should be apparent that there remains a need in the art for compositions, methods, and systems for STI chemical-mechanical polishing that can provide further reduced SiN removal rates, further increased SiO ₂ SiN selectivity, and more effective reduction of erosion on various density features of polished STI patterned wafers in STI Chemical and Mechanical Polishing (CMP) processes, in addition to providing high silicon dioxide removal rates.

Disclosure of Invention

The present invention provides STI polishing compositions that provide further reduced SiN removal rates, further improved SiO ₂ SiN selectivity, and more importantly, effectively reduced erosion on low density and narrow dimensional features of polished patterned wafers for Shallow Trench Isolation (STI) CMP applications over a wide pH range, including acidic, neutral, and basic pH conditions.

The disclosed Chemical Mechanical Polishing (CMP) composition for Shallow Trench Isolation (STI) CMP applications has a unique combination of using ceria coated inorganic oxide particles as an abrasive, a nonionic organic alcohol compound having multiple hydroxyl groups on the same molecule, and a chemical additive having at least one or dicarboxy functionality or at least two carboxyl functionalities and at least two hydroxyl groups on the same molecule.

Chemical additives having at least one, preferably at least two, carboxyl functional groups or dicarboxyl functional groups and at least two hydroxyl groups on the same molecule act to achieve STI CMP performance, as well as further reduced SiN removal rate, further improved SiO ₂: siN removal selectivity, and significantly reduced erosion on all dimensional features of the polished STI patterned wafer.

In one aspect, there is provided an STI CMP polishing composition comprising, consisting essentially of, or consisting of:

ceria coated inorganic oxide particles;

a nonionic organic alcohol compound having a plurality of hydroxyl groups on the same molecule;

A chemical additive having at least one, preferably at least two, carboxyl functions (or dicarboxyl functions) and at least two hydroxyl groups on the same molecule;

A water-soluble solvent;

and optionally a biocide, and

A pH regulator;

wherein the pH of the composition is from 2 to 12, preferably from 3 to 11, more preferably from 4 to 10, and most preferably from 5 to 9.

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

The water-soluble solvents include, but are not limited to, deionized (DI) water, distilled water, and alcoholic organic solvents.

The nonionic organic alcohol compound having a plurality of hydroxyl groups on the same molecule has a general molecular structure (a) as shown below:

(a)

in the general molecular structure of the nonionic organic alcohol compound, n is selected from 2 to 5,000, preferably n is 3 to 12, more preferably n is 5 to 7.

In these general molecular structures, R ₁、R₂、R₃ and R ₄ may be the same or different atoms or functional groups. They may be independently selected from the group consisting of hydrogen, alkyl groups, alkoxy groups, organic groups having one hydroxyl group, substituted organic sulfonic acids, substituted organic sulfonic acid salts, substituted organic carboxylic acids, substituted organic carboxylic acid salts, organic carboxylic acid esters, organic amine groups, and combinations thereof, wherein at least two or more, preferably four, of them are hydrogen atoms.

When R ₁、R₂、R₃ and R ₄ are the same and they are both hydrogen atoms, the nonionic organic alcohol compound has a plurality of hydroxyl functional groups. Some example molecular structures are listed below:

chemical additives having one carboxylic acid group and at least two hydroxyl groups on the same molecule have a general molecular structure including, but not limited to, the group of (b), (c), and (d) as shown below:

In the general molecular structure (b), n is selected from 1 to 5,000, 1 to 200 or 1 to 20, preferably n is 2 to 12, more preferably n is 3 to 6.

R ₁ and R ₂ may be the same or different atoms or functional groups. They may be independently selected from the group consisting of hydrogen, alkyl groups, alkoxy groups, organic groups having one hydroxyl group, substituted organic sulfonic acids, substituted organic sulfonic acid salts, substituted organic carboxylic acids, substituted organic carboxylic acid salts, organic carboxylic acid esters, organic amine groups, and combinations thereof, wherein at least one of R ₁ and R ₂ is hydrogen. Hydrogen.

R may be selected from the group consisting of hydrogen, alkyl, alkoxy, an organic group having one hydroxyl group, a substituted organic sulfonic acid salt, an organic amine group, and combinations thereof.

When R ₁ and R ₂ are both hydrogen atoms, the chemical additive carries an organic carboxyl group and at least two hydroxyl functional groups.

Preferably, R, R ₁ and R ₂ are all hydrogen.

In the general molecular structure (c), the six-membered ring may contain (1) all carbon-carbon single bonds, and one carboxylic acid and at least two hydroxyl groups directly bonded to the six-membered ring, or (2) one carbon-carbon double bond or two carbon-carbon double bonds or as an aromatic ring having a conjugated bond, and one carboxylic acid and at least two hydroxyl groups directly bonded to the six-membered ring.

In the general molecular structure (d), the six-membered ring may contain (1) four carbon-carbon single bonds, and R3 as an oxygen atom to form two carbon-oxygen single bonds in the six-membered ring, and one carboxylic acid and at least two hydroxyl groups directly bonded to the six-membered ring, or (2) one carbon-carbon double bond or two carbon-carbon double bonds, and one carboxylic acid and at least two hydroxyl groups directly bonded to the six-membered ring.

Chemical additives having two carboxylic acid groups and at least two hydroxyl groups on the same molecule have a general molecular structure including, but not limited to, the group of (e), (f), (g), (h), (i) and (j) shown below:

in the general molecular structure (e), n is selected from 1 to 5,000, 1 to 200 or 1 to 20, preferably n is 2 to 12, more preferably n is 3 to 6.

R ₁ and R ₂ may be the same or different atoms or functional groups. They may be independently selected from the group consisting of hydrogen, alkyl groups, alkoxy groups, organic groups having one hydroxyl group, substituted organic sulfonic acids, substituted organic sulfonic acid salts, substituted organic carboxylic acids, substituted organic carboxylic acid salts, organic carboxylic acid esters, organic amine groups, and combinations thereof, wherein at least one of R ₁ and R ₂ is hydrogen.

When R ₁ and R ₂ are both hydrogen atoms, the chemical additive bears two organic carboxyl groups and at least two hydroxyl functional groups.

Preferably, R ₁ and R ₂ are hydrogen.

In the general molecular structure (f), the six-membered ring may contain (1) all carbon-carbon single bonds on the ring, and two carboxylic acid groups and at least two hydroxyl groups directly bonded to the six-membered ring, or (2) one carbon-carbon double bond or two carbon-carbon double bonds or as an aromatic ring having a conjugated bond, and two carboxylic acid groups and at least two hydroxyl groups directly bonded to the six-membered ring.

In the general molecular structure (g), the six-membered ring may contain (1) four carbon-carbon single bonds and R ₄ as an oxygen atom, a nitrogen atom or an-NH-group to form two carbon-oxygen single bonds or carbon-nitrogen bonds in the six-membered ring, and two carboxylic acid groups and at least two hydroxyl groups directly bonded to the six-membered ring, or (2) one carbon-carbon double bond or two carbon-carbon double bonds, or have a conjugated chemical bond on the six-membered ring and two carboxylic acid groups and at least two hydroxyl groups directly bonded to the six-membered ring.

In the general molecular structure (h), R ₅ may be an oxygen atom, and two carboxylic acid groups and two hydroxyl groups are directly bonded to the five-membered ring.

In general molecular structure (i), R ₆ can be an alkyl group attached to an aromatic ring and to an aminoalkyldicarboxylic acid group. R ₇ and R ₈ are identical or different and are, for example, - (C ₂H₄-)_n -alkyl) in which n ranges from 1 to 6 and the two hydroxyl groups are directly bonded to the six-membered ring.

In general molecular structure (j), R ₉ and R ₁₀ may be the same or different and are alkyl groups, such as- (C ₂H₄-)_n) -in which n ranges from 1 to 6, at least two hydroxyl groups being directly bonded to the aromatic benzene ring.

Molecular structures of chemical additives with one organic carboxyl group and at least two hydroxyl functional groups include, but are not limited to:

molecular structures of chemical additives with two organic carboxyl groups and at least two hydroxyl functional groups include, but are not limited to:

In another aspect, a method of Chemical Mechanical Polishing (CMP) a substrate having at least one surface comprising silicon dioxide using the above-described Chemical Mechanical Polishing (CMP) composition in a Shallow Trench Isolation (STI) process is provided.

In another aspect, a system for Chemical Mechanical Polishing (CMP) a substrate having at least one surface comprising silicon dioxide using the above-described Chemical Mechanical Polishing (CMP) composition in a Shallow Trench Isolation (STI) process is provided.

The polished oxide film may be a Chemical Vapor Deposition (CVD), plasma Enhanced CVD (PECVD), high density deposition CVD (HDP), or spin-on oxide film.

The substrate disclosed above may further comprise a silicon nitride surface. SiO ₂ SiN has a removal selectivity of greater than 70, 80 or 90.

Detailed Description

In the global planarization of patterned STI structures, inhibiting SiN removal rates and increasing SiO ₂ SiN selectivity and providing more reduced and lower erosion on low density and narrow line features on polished STI patterned wafers are key factors to consider for advanced node STI CMP processes. Reduced erosion on low density and narrow line features will prevent current leakage between adjacent transistors. The higher erosion on low density and narrow line features affects transistor performance and device manufacturing yield. Therefore, it is important to reduce low density and narrow line erosion by further reducing SiN removal rates and increasing SiO ₂ SiN selectivity in STI CMP polishing compositions.

The present invention relates to Chemical Mechanical Polishing (CMP) compositions for Shallow Trench Isolation (STI) CMP applications.

More specifically, the disclosed Chemical Mechanical Polishing (CMP) composition for Shallow Trench Isolation (STI) CMP applications has inorganic oxide abrasive particles coated with ceria, a nonionic organic alcohol compound having multiple hydroxyl groups on the same molecule, and a unique combination of chemical additives to achieve STI CMP performance with further reduced SiN removal rates, further improved SiO ₂: siN selectivity, and more importantly, effectively reduced erosion on low density and narrow dimension features of the polished STI patterned wafer.

The use of the disclosed nonionic organic alcohol compounds and the disclosed chemical additives having at least one, preferably at least two, carboxyl functional groups (or dicarboxyl functional groups) and at least two hydroxyl groups on the same molecule provide synergistic benefits in achieving further reduced SiN film removal rates, further improved silicon SiO ₂ to SiN removal selectivity ratios (i.e., RR of SiO ₂ to RR of SiN), and importantly polishing further reduced erosion on low density and narrow line features of the patterned wafers.

ceria coated inorganic oxide particles;

A chemical additive having at least one or at least two carboxyl functional groups (or dicarboxyl functional groups) and at least two hydroxyl groups on the same molecule;

A water-soluble solvent;

And optionally

Biocidal agent, and

A pH regulator;

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

In the invention disclosed herein, the particle size (as measured by dynamic light scattering, DLS, technique) of these ceria coated inorganic metal oxide particles is in the range of 10nm to 1,000nm, with a preferred average particle size in the range of 20nm to 500nm, and a more preferred average particle size in the range of 50nm to 250 nm.

The concentration of these ceria coated inorganic oxide particles ranges from 0.01 wt% to 20 wt%, with a preferred concentration range from 0.05 wt% to 10 wt%, and a more preferred concentration range from 0.1 wt% to 5 wt%.

Preferred ceria coated inorganic oxide particles are ceria coated colloidal silica particles.

(a)

The STICMP composition contains 0.0001 wt.% to 2.0 wt.%, 0.0002 wt.% to 1.0 wt.%, or 0.0005 wt.% to 0.5 wt.% of a nonionic organic alcohol compound as a SiN film removal rate inhibitor and a low density characteristic erosion reducing agent.

The chemical additive has at least one or at least two carboxyl functional groups (or dicarboxyl functional groups) and at least two hydroxyl groups on the same molecule.

R ₁ and R ₂ may be the same or different and are each independently selected from the group consisting of hydrogen, alkyl, alkoxy, an organic group having one hydroxyl group, a substituted organic sulfonic acid salt, a substituted organic carboxylic acid salt, an organic carboxylic acid ester, an organic amine group, and combinations thereof, wherein at least one of R ₁ and R ₂ is hydrogen.

Preferably, R, R ₁ and R ₂ are all hydrogen.

In the general molecular structure (c), the six-membered ring may contain (1) all carbon-carbon single bonds, and one carboxylic acid and at least two hydroxyl groups directly bonded to the six-membered ring, or (2) one carbon-carbon double bond or two carbon-carbon double bonds or as an aromatic ring having a conjugated bond, and one carboxylic acid and at least two hydroxyl groups are directly bonded to the six-membered ring.

In the general molecular structure (d), the six-membered ring may contain (1) four carbon-carbon single bonds and R3 as an oxygen atom to form two carbon-oxygen single bonds in the six-membered ring and one carboxylic acid and at least two hydroxyl groups directly bonded to the six-membered ring, or (2) one carbon-carbon double bond or two carbon-carbon double bonds and one carboxylic acid and at least two hydroxyl groups directly bonded to the six-membered ring.

Preferably, R ₁ and R ₂ are hydrogen.

In general molecular structure (g), the six-membered ring may contain (1) four carbon-carbon single bonds, R ₄ may be an oxygen atom, a nitrogen atom, or a-NH-group to form two carbon-oxygen single bonds or carbon-nitrogen bonds in the six-membered ring, and two carboxylic acid groups and at least two hydroxyl groups directly bonded to the six-membered ring, or (2) one carbon-carbon double bond or two carbon-carbon double bonds, or have conjugated chemical bonds on the six-membered ring, and two carboxylic acid groups and at least two hydroxyl groups directly bonded to the six-membered ring.

In general molecular structure (i), R ₆ can be an alkyl group attached to an aromatic ring and to an aminoalkyldicarboxylic acid group. R ₇ and R ₈ are identical or different and are each alkyl radicals, for example- (C ₂H₄-)_n) -in which n ranges from 1 to 6 and the two hydroxyl groups are directly bonded to the six-membered ring.

In general molecular structure (j), R ₉ and R ₁₀ may be the same or different and are each alkyl groups, such as- (C ₂H₄-)_n) -in which n ranges from 1 to 6, at least two hydroxyl groups being directly bonded to the aromatic benzene ring.

Some examples of chemical additives with one organic carboxyl and at least two hydroxyl functional groups have the molecular structure shown below:

the molecular structure of some examples of chemical additives with two organic carboxyl groups and at least two hydroxyl functional groups is shown below:

The STI CMP composition contains 0.0001 wt% to 2.0 wt%, 0.0002 wt% to 1.0 wt%, 0.0005 wt% to 0.5wt%, or 0.0025 wt% to 0.015 wt% of a chemical additive-as a SiN film removal rate inhibitor and a low density feature erosion reducing agent.

The preferred water-soluble solvent is DI water.

The STI CMP composition may contain 0.0001 wt% to 0.05 wt%, preferably 0.0005 wt% to 0.025 wt%, and more preferably 0.001 wt% to 0.01 wt% biocide.

Biocides include, but are not limited to, kathon ^TM、Kathon^TM CG/ICP II from Dupont/Dow Chemical Co., bioban from Dupont/Dow Chemical Co. They have the active ingredient 5-chloro-2-methyl-4-isothiazolin-3-one, 2-n-octyl-4-isothiazolin-3-one.

The STICMP compositions may contain a pH adjustor.

The STI polishing composition can be adjusted to an optimal pH using acidic or neutral or basic pH adjusters.

PH adjusting agents include, but are not limited to, nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid, other inorganic or organic acids, and mixtures thereof, to adjust the pH toward a more acidic direction.

The pH adjustor also includes basic pH adjustor such as sodium hydride, potassium hydroxide, ammonium hydroxide, tetraalkylammonium hydroxide, organic quaternary ammonium hydroxide, organic amine, and other chemical agents that may be used to adjust pH in a more basic direction.

The STI CMP composition contains 0 wt.% to 1 wt.%, preferably 0.01 wt.% to 0.5 wt.%, and more preferably 0.1 wt.% to 0.25 wt.% pH adjustor.

In another aspect, a method of Chemical Mechanical Polishing (CMP) a substrate having at least one surface comprising silicon dioxide using the above-described Chemical Mechanical Polishing (CMP) composition in a Shallow Trench Isolation (STI) process is provided. The polished oxide film may be a CVD oxide, PECVD oxide, high density oxide or spin-on oxide film.

The following non-limiting examples are provided to further illustrate the invention.

CMP method

In the examples given below, CMP experiments were performed using the procedures and experimental conditions given below.

Vocabulary list

Component (A)

Ceria coated silica, used as an abrasive, has an average particle size of about 120 nanometers (nm).

Ceria coated silica particles (of different sizes) were provided by JGC inc. In japan and prepared by the methods described in JP2013119131 and JP2013133255, WO 2016/159167, japanese patent application JP2015-169967, and JP 2015-183942.

Chemical additives such as maltitol, mucic acid, tartaric acid and all other chemical raw materials are supplied by Millipore Sigma, st.

TEOS tetraethyl orthosilicate

Polishing pad-polishing pad IC 1010 and other pads, supplied by DOW, inc.

Parameters (parameters)

Universal use

Or A. ANG. Length units

BP back pressure in psi

CMP chemical mechanical planarization = chemical mechanical polishing

CS Carrier speed

DF: down force: pressure applied during CMP, unit: psi

Min is min

Ml/ml

MV: millivolt

MM millimoles

Psi: pounds per square inch

PS, platen rotation speed of polishing apparatus in rpm

SF is the flow rate of the composition, ml/min

Wt.% (of the listed components)

TEOS SiN Selectivity (TEOS removal Rate)/(SiN removal Rate)

HDP high density plasma deposited TEOS

TEOS or HDP removal Rate measured at a given downforce. In the above examples, the CMP apparatus had a downforce of 2.0, 3.0, or 4.0psi.

SiN removal rate measured at a given downforce. In the example listed, the CMP apparatus had a downforce of 3.0psi.

Metrology of

Films were measured using RESMAP CDE, model 168, manufactured by CREATIVE DESIGN ENGINEERING, inc.,20565Alves Dr, cupertino, CA, 95014. The ResMap device is a four-point probe sheet resistance device. The film was subjected to a 5mm edge exclusion 49 spot diameter scan.

CMP equipment

The CMP apparatus used was 200mm Mirra or 300mm Reflexion manufactured by APPLIED MATERIALS,3050BOWERES AVENUE,SANTA CLARA,CALIFORNIA,95054. IC1000 pads provided by DOW, inc.,451 bellevile Rd, newark, DE 19713 were used on platen 1 for blanket and patterned wafer study.

The IC1010 pad or other pad is worn in by trimming the pad for 18 minutes. A downward force of 7 pounds was applied to the conditioner. To qualify equipment set-up and pad run-in, use under baseline conditions

STI2305 composition (supplied by Versum Materials inc.) polishes four TEOS monitors.

Wafer with a plurality of wafers

Polishing experiments were performed using PECVD or LECVD or HD TEOS wafers and SiN wafers, the patterned wafers being MIT864 oxide patterned wafers. These blanket and patterned wafers were purchased from Silicon Valley Microelectronics,2985Kifer Rd, SANTA CLARA, CA 95051.

Polishing experiment

In blanket wafer studies, oxide blanket wafers and SiN blanket wafers were polished under baseline conditions. The equipment baseline conditions were platen speed, 87rpm, head speed 93rpm, membrane pressure, 3.0psi, composition flow rate, 200ml/min, 100% in situ trim using Saesol E disk.

These polished patterned wafers (MIT 864) were measured on a Veeco VX 300 profiler/AFM instrument.

TEOS obtained from the STICMP polishing composition: the SiN selectivity ratio (removal rate of TEOS)/(removal rate of SiN) is adjustable. Lower or reduced P200 oxide trench loss rates indicate improved topography data, such as narrow feature lines and reduced erosion on lower density features.

The different sizes of oxide trench RR/blanket oxide film RR ratios are key parameters in determining whether an oxide polishing composition can provide lower oxide dishing when used in oxide CMP polishing applications. In general, the smaller this ratio, the lower the oxide trench recess.

Example 1

In example 1, STI polishing reference 1 and 3 (ref.1 and ref.3) compositions were prepared using 0.2 wt% ceria coated silica, 0.00039 wt% Bioban 425 as biocide, 0.8 millimoles (mM) maltitol (or 0.28 wt%) or 0.8mM D-sorbitol (or 0.15 wt%) as nonionic organic alcohol compound (alcohol) and deionized water (at pH 7), respectively. Ref.2 was prepared by adding 0.024mM adipic acid (not a claimed chemical additive) to Ref.1. Different chemical additives were added to ref.1 at 0.024mM to obtain working example comparative examples 1-6. For better comparison purposes, the concentrations of nonionic organic alcohols and chemical additives are in mV.

The removal rates (RR in angstroms/min) of TEOS (silicon oxide blanket wafer) and SiN (blanket wafer) were measured, as well as the P200 trench loss rate on polished MIT 864 patterned wafers. The ratio of P200 trench loss rate/blanket RR is calculated. The test results are shown in Table 1. The ratio of P200 trench loss rate/blanket RR was calculated and is also listed in table 1.

TABLE 1 film RR (angstroms per minute), TEOS: siN selectivity, P200 trench loss rate (angstroms per minute) and ratio of P200 oxide trench loss rate/blanket oxide RR

As shown in table 1, most of the data for the compositions using 0.8mM nonionic organic alcohol compound (maltitol or D-sorbitol) and 0.024mM chemical additive showed effectively reduced SiN RR and improved SiO ₂: siN film selectivity, improved P200 trench loss rate (angstroms/min) and P200 trench loss rate. For STI polishing, a reduced SiN RR is desirable and when combined with a low trench loss rate, can provide low erosion on the polished oxide patterned wafer.

Note that adipic acid is not a disclosed chemical additive. It is used as a reference only. Adipic acid is structurally similar to mucic acid but has no hydroxyl groups. The composition containing adipic acid reduced nitride removal and improved SiO ₂ vs SiN selectivity, however the composition had poor P200 trench loss rate (angstroms/min) and worst P200 trench loss rate (angstroms/min) to blanket removal rate ratio.

Thus, chemical additives that do not have at least one or at least two carboxyl functional groups and at least two hydroxyl groups on the same molecule cannot improve the P200 trench loss rate (angstroms/min) and the ratio of P200 trench loss rate (angstroms/min) to blanket removal rate.

Example 2

In example 2, all polishing compositions used 0.2 wt.% ceria coated silica, 0.00039 wt.% Bioban 425 as biocide, and deionized water.

The CMP polishing compositions in Table 2 were prepared using (1) a fixed concentration of a nonionic organic alcohol compound (alcohol) and a chemical additive, but at various different pH's, a fixed concentration of a nonionic organic alcohol compound (alcohol) and various concentrations of a chemical additive at a fixed pH, or a fixed concentration of a chemical additive and various concentrations of a nonionic organic alcohol compound (alcohol) at a fixed pH.

The removal rates (RR in angstroms/min) of oxide (blanket wafer) and SiN (blanket wafer) were measured as well as the P200 trench loss rate on polished MIT 864 patterned wafer. The test results are shown in Table 2.

TABLE 2 film RR (angstroms/min), TEOS: siN selectivity, P200 trench loss rate (angstroms/min) and P200 oxide trench loss rate/overlay oxide RR ratio

The data in Table 2 shows effectively reduced SiN RR and increased SiO ₂ SiN film selectivity, while having an improved or sustained P200 trench loss rate (angstroms/min) and a ratio of P200 oxide trench loss rate (angstroms/min) to blanket oxide removal rate.

As demonstrated in the working examples, the use of a chemical additive having at least one or at least two carboxyl functional groups (or dicarboxy functional groups) and at least two hydroxyl groups on the same molecule with a nonionic organic alcohol compound having multiple hydroxyl groups on the same molecule can reduce nitride rate and improve selectivity while providing low erosion on various dimensional features of the polished STI patterned wafer and low oxide trench recessing for the polished oxide patterned wafer.

The embodiments of the invention listed above, including working examples, are examples of the many embodiments that can be made up of the invention. It is contemplated that many other configurations of the method may be used, and that the materials used in the method may be selected from many materials other than those specifically disclosed.

Claims

1. A chemical-mechanical planarization polishing composition comprising:

From 0.01 wt% to 20wt%, from 0.05 wt% to 10 wt%, or from 0.1 wt% to 5 wt% ceria coated inorganic oxide particles;

0.0001 to 2.0 wt%, 0.0002 to 1.0 wt%, or 0.0005 to 0.5 wt% of a nonionic organic alcohol compound having a plurality of hydroxyl groups on the same molecule;

0.0001 to 2.0 wt%, 0.0002 to 1.0 wt%, 0.0005 to 0.5 wt% or 0.0025 to 0.015 wt% of a chemical additive having at least one or at least two carboxyl functional groups and at least two hydroxyl groups on the same molecule;

A water-soluble solvent;

And optionally

0.00 To 0.05, 0.0005 to 0.025 or 0.001 to 0.01 wt% of a biocide, and

0 To 1 wt%, 0.01 to 0.5 wt% or 0.1 to 0.25 wt% of a pH adjuster;

Wherein the composition has a pH of 2 to 12, 3 to 11, 4 to 10, or 5 to 9.

2. The chemical mechanical polishing composition of claim 1, wherein the ceria coated inorganic oxide particles are selected from the group consisting of ceria coated silica, ceria coated colloidal silica, ceria coated alumina, ceria coated titania, ceria coated zirconia, and combinations thereof.

3. The chemical mechanical polishing composition of claim 1, wherein the water-soluble solvent is selected from the group consisting of Deionized (DI) water, distilled water, and alcoholic organic solvents.

4. The chemical mechanical polishing composition according to claim 1, wherein the nonionic organic alcohol compound having a plurality of hydroxyl groups on the same molecule has a general molecular structure (a) as shown below:

(a)

Wherein the method comprises the steps of

N is selected from 2 to 5,000, 3 to 12 or 5 to 7;

R ₁、R₂、R₃ and R ₄ may be the same or different atoms or functional groups and may be independently selected from hydrogen, alkyl, alkoxy, organic groups having one or more hydroxyl groups, substituted organic sulfonic acids, substituted organic sulfonic acid salts, substituted organic carboxylic acids, substituted organic carboxylic acid salts, organic carboxylic acid esters, organic amine groups, and combinations thereof.

5. The chemical mechanical polishing composition according to claim 1, wherein the nonionic organic alcohol compound having a plurality of hydroxyl groups on the same molecule has a general molecular structure (a) as shown below:

(a)

Wherein the method comprises the steps of

N is selected from 2 to 5,000, 3 to 12 or 5 to 7, and

At least two of R ₁、R₂、R₃ and R ₄ are hydrogen atoms.

6. The chemical mechanical polishing composition according to claim 1, wherein the nonionic organic alcohol compound having a plurality of hydroxyl groups on the same molecule has a general molecular structure (a) as shown below:

(a)

Wherein the method comprises the steps of

N is selected from 2 to 5,000, 3 to 12 or 5 to 7, and

R ₁、R₂、R₃ and R ₄ are all hydrogen atoms.

7. The chemical mechanical polishing composition of claim 1, wherein the nonionic organic alcohol compound having a plurality of hydroxyl groups on the same molecule is selected from the group consisting of D-sorbitol, mannitol, dulcitol, maltitol, lactitol, and combinations thereof.

8. The chemical mechanical polishing composition of claim 1, wherein the chemical additive has at least one carboxyl functional group and at least two hydroxyl groups on the same molecule and has a general molecular structure selected from the group consisting of:

Wherein the method comprises the steps of

In (b), n is selected from 1 to 5,000, 1 to 200, or 1 to 20, preferably n is 2 to 12, more preferably n is 3 to 6;R ₁ and R ₂ may be the same or different and are each independently selected from hydrogen, alkyl, alkoxy, an organic group having one or more hydroxyl groups, a substituted organic sulfonic acid salt, a substituted organic carboxylic acid salt, an organic carboxylic acid ester, an organic amine group, and combinations thereof, wherein at least one of R ₁ and R ₂ is hydrogen, R may be selected from hydrogen, alkyl, alkoxy, an organic group having one or more hydroxyl groups, a substituted organic sulfonic acid salt, an organic amine group, and combinations thereof, preferably R ₁ and R ₂ are hydrogen, or R, R ₁ and R ₂ are all hydrogen;

In (c), the six-membered ring may contain (1) all carbon-carbon single bonds, and one carboxylic acid and at least two hydroxyl groups directly bonded to the six-membered ring, or (2) one carbon-carbon double bond, two carbon-carbon double bonds, or as an aromatic ring having a conjugated bond, and one carboxylic acid and at least two hydroxyl groups directly bonded to the six-membered ring;

In (d), the six-membered ring may contain (1) four carbon-carbon single bonds and R ₃ as oxygen atoms to form two carbon-oxygen single bonds, one carboxylic acid and at least two hydroxyl groups directly bonded to the six-membered ring, or (2) one or two carbon-carbon double bonds, and one carboxylic acid and at least two hydroxyl groups directly bonded to the six-membered ring.

9. The chemical mechanical polishing composition of claim 1, wherein the chemical additive has at least two carboxyl functional groups and at least two hydroxyl groups on the same molecule and has a general molecular structure selected from the group consisting of:

Wherein the method comprises the steps of

In (e), n is selected from 1 to 5,000, 1 to 200, or 1 to 20, preferably n is 2 to 12, more preferably n is 3 to 6;R ₁ and R ₂ may be the same or different atoms or functional groups, and each is independently selected from hydrogen, alkyl, alkoxy, an organic group having one or more hydroxyl groups, a substituted organic sulfonic acid salt, a substituted organic carboxylic acid salt, an organic carboxylic acid ester, an organic amine group, and combinations thereof, wherein at least one of R ₁ and R ₂ is hydrogen, preferably R ₁ and R ₂ are hydrogen;

In (f), the six-membered ring may contain (1) all carbon-carbon single bonds on the ring, and two carboxylic acid groups and at least two hydroxyl groups directly bonded to the six-membered ring, or (2) one carbon-carbon double bond, two carbon-carbon double bonds, or as an aromatic ring having a conjugated bond, and two carboxylic acid groups and at least two hydroxyl groups directly bonded to the six-membered ring;

In (g), the six-membered ring may contain (1) four carbon-carbon single bonds, R ₄ may be an oxygen atom, a nitrogen atom, or an-NH-group to form two carbon-oxygen single bonds or carbon-nitrogen bonds, and two carboxylic acid groups and at least two hydroxyl groups bonded directly to the six-membered ring, or (2) one carbon-carbon double bond, two carbon-carbon double bonds, or a conjugated chemical bond on the six-membered ring, and two carboxylic acid groups and at least two hydroxyl groups bonded directly to the six-membered ring;

in (h), R ₅ may be an oxygen atom, and two carboxylic acid groups and two hydroxyl groups are directly bonded to the five-membered ring;

In (i), R ₆ may be an alkyl group attached to an aromatic ring and to an aminoalkyldicarboxylic acid group, R ₇ and R ₈ may be the same or different and are each an alkyl group as- (C ₂H₄-)_n) -in which n is in the range of 1 to 6 and two hydroxy groups are directly bonded to the six-membered ring, and

In (j), R ₉ and R ₁₀ may be the same or different and are each alkyl, such as- (C ₂H₄-)_n) -in which n ranges from 1 to 6, at least two hydroxyl groups being directly bonded to the aromatic benzene ring.

10. The chemical mechanical polishing composition of claim 1 wherein the chemical additive has at least one carboxyl functional group and at least two hydroxyl groups on the same molecule and is selected from the group consisting of D- (-) -quinic acid, gluconic acid, D-glucuronic acid, 2, 3-dihydroxybenzoic acid, 2, 4-dihydroxybenzoic acid, 2, 5-dihydroxybenzoic acid, 2, 6-dihydroxybenzoic acid, 3, 4-dihydroxybenzoic acid, 3, 5-dihydroxybenzoic acid, 1, 4-dihydroxy-2-naphthoic acid, and combinations thereof.

11. The chemical mechanical polishing composition of claim 1 wherein the chemical additive has at least one carboxyl function and at least two hydroxyl groups on the same molecule and is selected from the group consisting of D- (-) -quinic acid, gluconic acid, D-glucuronic acid, and combinations thereof.

12. The chemical mechanical polishing composition of claim 1, wherein the chemical additive having at least two carboxyl functional groups and at least two hydroxyl groups on the same molecule is selected from the group consisting of tartaric acid, mucic acid, 3, 4-dihydroxy-1, 5-cyclohexadiene-1, 4-dicarboxylic acid, (1R, 6S) -dihydroxycyclohexane-2, 4-diene-1, 4-dicarboxylic acid, 4, 5-cis-dihydrodiol phthalate, 2, 5-dihydroxy-1, 4-benzenedicarboxylic acid, (carboxymethyl- (2, 5-dihydroxy-benzyl) -amino) -acetic acid, dihydroxymalonic acid, 3, 4-dihydroxy-2, 5-furandicarboxylic acid, and combinations thereof.

13. The chemical mechanical polishing composition of claim 1 wherein the chemical additive having at least two carboxyl functional groups and at least two hydroxyl groups on the same molecule is selected from tartaric acid, mucic acid, and combinations thereof.

14. The chemical mechanical polishing composition of claim 1 wherein the composition comprises ceria coated silica, tartaric acid, gluconic acid, mucic acid, D-glucuronic acid, D- (-) -quinic acid, or a combination thereof, and maltitol, D-sorbitol, lactitol, or a combination thereof.

15. The chemical mechanical polishing composition of claim 1, wherein the composition comprises 0.1 wt.% to 5 wt.% ceria coated silica, 0.0025 wt.% to 0.015 wt.% tartaric acid, gluconic acid, mucic acid, D-glucuronic acid, D- (-) -quinic acid, or a combination thereof, and 0.0005 wt.% to 0.5 wt.% maltitol, D-sorbitol, lactitol, or a combination thereof.

16. The chemical mechanical polishing composition of claim 1, wherein the composition comprises:

From 0.05 to 10 wt% or from 0.1 to 5 wt% ceria coated inorganic oxide particles;

0.0002 to 1.0 wt% or 0.0005 to 0.5 wt% of a nonionic organic alcohol compound having a plurality of hydroxyl groups on the same molecule;

0.0005 wt% to 0.5 wt% or 0.0025 wt% to 0.015 wt% of a chemical additive having at least one or at least two carboxyl functional groups and at least two hydroxyl groups on the same molecule;

A water-soluble solvent;

And optionally

0.0005 Wt% to 0.025 wt% or 0.001 wt% to 0.01 wt% biocide, and

0.01 To 0.5 wt% or 0.1 to 0.25 wt% of a pH adjuster;

Wherein the composition has a pH of 4 to 10 or 5 to 9.

17. The chemical mechanical polishing composition of claim 1, wherein the composition has a pH of 2 to 12 or 3 to 11.

18. The chemical mechanical polishing composition of claim 1, wherein the composition has a pH of 3 to 11 or 4 to 10.

19. The chemical mechanical polishing composition of claim 1, wherein the composition has a pH of 4 to 10 or 5 to 9.

20. The chemical mechanical polishing composition of claim 1 wherein the composition further comprises at least one member selected from the group consisting of biocides having an active ingredient of 5-chloro-2-methyl-4-isothiazolin-3-one, or 2-n-octyl-4-isothiazolin-3-one, and pH modifiers for acidic pH conditions selected from the group consisting of nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid, other inorganic or organic acids, and mixtures thereof, or pH modifiers for basic pH conditions selected from the group consisting of sodium hydride, potassium hydroxide, ammonium hydroxide, tetraalkylammonium hydroxide, organic quaternary ammonium hydroxides, organic amines, and combinations thereof.

21. A method of Chemical Mechanical Polishing (CMP) a semiconductor substrate having at least one surface comprising a silicon oxide film, comprising:

Providing the semiconductor substrate;

providing a polishing pad;

providing a Chemical Mechanical Polishing (CMP) composition of any one of claims 1 to 20;

Contacting a surface of the semiconductor substrate with the polishing pad and the chemical mechanical polishing composition, and

Polishing the at least one surface comprising silicon dioxide.

22. The method of claim 21, wherein the silicon oxide film is selected from Chemical Vapor Deposition (CVD), plasma Enhanced CVD (PECVD), high density deposition CVD (HDP), or spin-on silicon oxide film.

23. The method of claim 21, wherein the semiconductor substrate further comprises a surface comprising silicon nitride and the SiO ₂ SiN removal selectivity is greater than 70, 80, or 90.

24. A system for Chemical Mechanical Polishing (CMP) a semiconductor substrate having at least one surface comprising a silicon oxide film, comprising:

a. the semiconductor substrate;

b. The Chemical Mechanical Polishing (CMP) composition of any one of claims 1 to 20;

c. A polishing pad;

wherein the at least one surface comprising a silicon oxide film is in contact with the polishing pad and the chemical-mechanical polishing composition.

25. The system of claim 24, wherein the silicon oxide film is selected from Chemical Vapor Deposition (CVD), plasma Enhanced CVD (PECVD), high density deposition CVD (HDP), or spin-on silicon oxide film.

26. The system of claim 24, wherein the semiconductor substrate further comprises a surface comprising silicon nitride and the SiO ₂ SiN removal selectivity is greater than 70, 80, or 90.