SLURRY COMPOSITION FOR CHEMICAL MECHANICAL POLISHING

A slurry composition for a chemical mechanical polishing (CMP) process, the slurry composition including an organic polishing booster including an iminium cation; a carrier; and optionally including inorganic polishing particles, wherein, when included, the inorganic polishing particles are included in the slurry composition in an amount of less than 0.1% by weight, based on a total weight of the slurry composition.

CROSS-REFERENCE TO RELATED APPLICATION

Korean Patent Application No. 10-2020-0078045, filed on Jun. 25, 2020, in the Korean Intellectual Property Office, and entitled: “Slurry Composition for Chemical Mechanical Polishing,” is incorporated by reference herein in its entirety.

BACKGROUND

Embodiments relate to a slurry composition for a chemical mechanical polishing (CMP) process.

2. Description of the Related Art

Polishing agents (or abrasives), such as inorganic polishing particles, may be added to a slurry composition for a CMP process.

SUMMARY

The embodiments may be realized by providing a slurry composition for a chemical mechanical polishing (CMP) process, the slurry composition including an organic polishing booster including an iminium cation; a carrier; and optionally including inorganic polishing particles, wherein, when included, the inorganic polishing particles are included in the slurry composition in an amount of less than 0.1% by weight, based on a total weight of the slurry composition.

The embodiments may be realized by providing a slurry composition for a chemical mechanical polishing (CMP) process, the slurry composition including an organic polishing booster; a surfactant; and a carrier, wherein the organic polishing booster is included in the slurry composition in an amount of about 10 ppm to about 10,000 ppm by weight, and the slurry composition is essentially free of inorganic polishing particles.

The embodiments may be realized by providing a slurry composition for a polysilicon polishing process, the slurry composition including an organic polishing booster including an iminium cation; a surfactant; a pH control agent; and a carrier, wherein a pH of the slurry composition is in a range of about 2 to about 5, and the slurry composition is essentially free of inorganic polishing particles and a dispersion stabilizer for uniform distribution of the inorganic polishing particles.

DETAILED DESCRIPTION

FIG. 1is a perspective view of a polishing apparatus100capable of performing a chemical mechanical polishing (CMP) process.

Referring toFIG. 1, the polishing apparatus100may include a platen120having a rotating disc shape on which a polishing pad110is placed. The platen120may be capable of rotating about a central axis125thereof. In an implementation, a motor121may turn a driving axis124to rotate the platen120. The polishing pad110may be a polishing pad having at least two layers including an outer polishing layer112and a backing layer114that is more flexible than the outer polishing layer112.

The polishing apparatus100may include a slurry port130configured to dispense a polishing agent132(e.g., slurry) toward the polishing pad110. The polishing apparatus100may include a polishing pad conditioner160configured to condition the polishing pad110so that the polishing pad110may be maintained in a consistent polishing state.

The polishing apparatus100may include at least one carrier head140. The carrier head140may be configured to hold a substrate10against the polishing pad110The carrier head140may independently control polishing parameters (e.g., pressure) associated with each substrate.

In an implementation, the carrier head140may include a retaining ring142to hold the substrate10under a flexible membrane. The carrier head140may include a plurality of pressurizable chambers, which may be defined by the flexible membrane and controlled independently. The plurality of pressurizable chambers may independently apply controllable pressures to associated zones of the flexible membrane and the substrate10.

The carrier head140may hang from a support structure150(e.g., a carousel or a track) and be connected to a carrier head rotational motor154by a driving axis152, and thus, the carrier head140may rotate about a central axis155. In an implementation, the carrier head140may oscillate in a lateral direction, e.g., on a slider on the carousel or the track or oscillate due to rotary oscillation of the carousel. During operation, the platen120may rotate about the central axis125thereof, and the carrier head140may rotate the central axis155thereof and be translated across a top surface of the polishing pad110in the lateral direction.

In an implementation, only one carrier head140may be included, as is illustrated inFIG. 1, or at least two carrier heads for maintaining additional substrates may be provided to efficiently use a surface area of the polishing pad110.

The polishing apparatus100may also include a control system configured to control rotation of the platen120. The control system may include a controller190(e.g., a general-use programmable digital computer), an output device192(e.g., a monitor), and an input device194(e.g., a keyboard).

In an implementation, as illustrated inFIG. 1, the control system may be connected only to the motor121, or the control system may be also connected to the carrier head140and control a pressure or rotation speed of the carrier head140. In an implementation, the control system may be connected to the slurry port130and control the supplying of slurry.

An embodiment provides a slurry composition for a CMP process, which may be used for the polishing apparatus100.

The slurry composition may include an organic polishing booster and a carrier.

Organic Polishing Booster

The organic polishing booster may include an iminium cation. In an implementation, the iminium cation may include, e.g., an imidazolium cation, a pyridinium cation, a triazolium cation, or a guanidinium cation. As used herein, the term “or” is not an exclusive term, e.g., “A or B” would include A, B, or A and B.

In an implementation, the organic polishing booster may include an imidazolium cation represented by Formula A1.

In Formula A1, RA1and RA2may each independently be or include, e.g., hydrogen, a C1 to C20 straight-chain alkyl group, a C3 to C20 branched alkyl group, a C3 to C20 cycloalkyl group, a C2 to C20 alkenyl group, a C2 to C20 alkynyl group, a C6 to C20 aryl group, a C3 to C20 allyl group, a C1 to C20 alkoxy group, a C6 to C20 aryloxy group, or a combination thereof. In an implementation, RA1and RA2may be separate or may be linked to each other to form a ring.

In an implementation, the imidazolium cation may be represented by, e.g., Formula 1 or Formula 2.

In Formulae 1 and 2, R1, R2, R3, and R4may each independently be or include, e.g., hydrogen, a C1 to C20 straight-chain alkyl group, a C3 to C20 branched alkyl group, a C3 to C20 cycloalkyl group, a C2 to C20 alkenyl group, a C2 to C20 alkynyl group, a C6 to C20 aryl group, a C3 to C20 allyl group, a C1 to C20 alkoxy group, a C6 to C20 aryloxy group, or a combination thereof. In an implementation, R1and R2may be separate or may be linked to each other to form a ring, and R3and R4may be separate or may be linked to each other to form a ring.

In an implementation, the pyridinium cation may be represented by, e.g., Formula 3.

In an implementation, the triazolium cation may be represented by, e.g., Formula A2 or Formula A3.

In Formulae A2 and A3, RA3, RA4, RA5, and RA6may each independently be or include, e.g., hydrogen, a C1 to C20 straight-chain alkyl group, a C3 to C20 branched alkyl group, a C3 to C20 cycloalkyl group, a C2 to C20 alkenyl group, a C2 to C20 alkynyl group, a C6 to C20 aryl group, a C3 to C20 allyl group, a C1 to C20 alkoxy group, a C6 to C20 aryloxy group, or a combination thereof. In an implementation, RA3and RA4may be separate or may be linked to each other to form a ring, and RA5and RA6may be separate or may be linked to each other to form a ring.

In an implementation, the triazolium cation may be represented by, e.g., Formula 4, Formula 5, or Formula 6

In Formulae 4 to 6, R6, R7, R8, R9, R10, and R11may each independently be or include, e.g., hydrogen, a C1 to C20 straight-chain alkyl group, a C3 to C20 branched alkyl group, a C3 to C20 cycloalkyl group, a C2 to C20 alkenyl group, a C2 to C20 alkynyl group, a C6 to C20 aryl group, a C3 to C20 allyl group, a C1 to C20 alkoxy group, a C6 to C20 aryloxy group, or a combination thereof. In an implementation, R6and R7may be separate or may be linked to each other to form a ring, R8and R9may be separate or may be linked to each other to form a ring, and R10and R11may be separate or may be linked to each other to form a ring.

In an implementation, the guanidinium cation may be represented by, e.g., Formula 7.

In Formula 7, R12, R13, R14, R15, R16, and R17may each independently be or include, e.g., hydrogen, a C1 to C20 straight-chain alkyl group, a C3 to C20 branched alkyl group, a C3 to C20 cycloalkyl group, a C2 to C20 alkenyl group, a C2 to C20 alkynyl group, a C6 to C20 aryl group, a C3 to C20 allyl group, a C1 to C20 alkoxy group, a C6 to C20 aryloxy group, or a combination thereof. In an implementation, and any two (e.g., adjacent ones) of R12, R13, R14, R15, R16, and R17may be separate or may be linked to each other to form a ring.

In an implementation, in Formulae 1 to 7, the C1 to C20 straight-chain alkyl group may each independently include, e.g., methyl, ethyl, n-propyl, n-butyl, or n-pentyl.

In an implementation, in Formulae 1 to 7, the C3 to C20 cycloalkyl group may each independently include, e.g., cyclopropyl, cyclobutyl, cyclopentyl, or cyclohexyl.

In an implementation, in Formulae 1 to 7, the C2 to C20 alkenyl group may each independently include, e.g., ethylenyl, propylenyl, or butylenyl.

In an implementation, in Formulae 1 to 7, the C6 to C20 aryl group may each independently include, e.g., phenyl, naphthyl, tolyl, or xylyl.

In an implementation, the organic polishing booster of Formulae 1 to 7 described above may be a monomer, which may be polymerized depending on a substituent. In an implementation, when the substituent has a vinyl group (e.g., —CH═CH2) including a double bond, an oligomer or a polymer may be formed due to polymerization. In an implementation, the organic polishing booster may include the oligomer or the polymer.

In an implementation, R2in Formula 1 may be a vinyl group, the compound of Formula 1 may have a structure represented by Formula 1a, and may be polymerized to obtain a compound including a moiety represented by Formula 8′ (e.g., a polymer or oligomer including “m” number of repeating units).

In an implementation, R7of Formula 4 may be a vinyl group, the compound of Formula 4 may have a structure represented by Formula 4a, and may be polymerized to obtain a compound including moiety represented by Formula 9′ (e.g., a polymer or oligomer including “m” number of repeating units).

In an implementation, R5of Formula 3 may be a vinyl group, the compound of Formula 3 may have a structure represented by Formula 3a, and may be polymerized to obtain a compound including a moiety represented by Formula 10′ (e.g., a polymer or oligomer including “m” number of repeating units).

In an implementation, an oligomer or polymer obtained by polymerizing the organic polishing booster of Formulae 1 to 7 may have a weight-averaged molecular weight of, e.g., about 3,000 to about 100,000. In an implementation, the oligomer or the polymer may have a weight-averaged molecular weight of, e.g., about 5,000 to about 90,000, about 8,000 to about 80,000, about 10,000 to about 70,000, about 15,000 to about 60,000, or about 20,000 to about 50,000.

The weight-averaged molecular weight may be, e.g., measured by gel permeation chromatography (GPC) using polystyrene as a standard.

The organic polishing booster may be included in the slurry composition for the CMP process in an amount of, e.g., about 10 ppm to about 10,000 ppm by weight. In an implementation, the organic polishing booster may be included in an amount of, e.g., about 30 ppm to about 9,000 ppm by weight, about 100 ppm to about 8,000 ppm by weight, about 150 ppm to about 7,000 ppm by weight, about 300 ppm to about 6,500 ppm by weight, about 500 ppm to about 6,000 ppm by weight, about 800 ppm to about 5,500 ppm by weight, or about 1000 ppm to about 5,000 ppm by weight.

Including a sufficiently high amount of the organic polishing booster in the slurry composition for the CMP process may help ensure that a polishing effect is satisfactory. Including a sufficiently low amount of the organic polishing booster in the slurry composition for the CMP process may facilitate controlling of a polishing rate.

The carrier may be a suitable liquid capable of substantially uniformly dispersing the organic polishing booster. The carrier may be, e.g., an aqueous solvent or an organic solvent.

The amount of the carrier may be a residual portion or balance amount, excluding the organic polishing booster and other components to be described below.

In an implementation, the slurry composition for the CMP process may include inorganic polishing particles in an amount of, e.g., less than about 0.1% by weight. The inorganic polishing particles may be suitable inorganic particles (e.g., metal oxide particles), which are widely used for a slurry composition for a CMP process.

In an implementation, the slurry composition for the CMP process may include the inorganic polishing particles in an amount, e.g., of less than about 0.08% by weight, less than about 0.05% by weight, less than about 0.03% by weight, less than about 0.01% by weight, less than about 0.008% by weight, less than about 0.005% by weight, less than about 0.003% by weight, less than about 0.001% by weight, less than about 0.0008% by weight, less than about 0.0005% by weight, less than about 0.0003% by weight, or less than about 0.0001% by weight (e.g., based on a total weight of the slurry composition).

In an implementation, the slurry composition for the CMP process may not include the inorganic polishing particles (e.g., may be essentially free of inorganic polishing particles). In an implementation, the slurry composition for the CMP process may not include metal oxide particles. In an implementation, the slurry composition for the CMP process may not include any of silica, alumina, ceria, titania, zirconia, magnesia, germania, and mangania.

Here, when some particles are referred to as being ‘not included,’ or the composition being “essentially free of” the particles, it indicates that the particles are not intentionally added, but it does not indicate that the particles are not present at all or exist below a detection limit. Accordingly, the slurry composition for the CMP process may include the particles in an amount similar to that of unavoidable impurities.

Depending on polishing conditions, some inorganic polishing particles included in a slurry composition for a CMP process may damage a semiconductor device formed on a polishing object. For example, the inorganic polishing particles may damage layers, wirings, and patterns formed on the polishing object. Alternatively, even when a polishing process ends, the inorganic polishing particles may not be sufficiently removed and could cause contamination.

In addition, some inorganic polishing particles could reduce the lifespan of a polishing pad (refer to110inFIG. 1) used for a polishing process, and the inorganic polishing particles may become the cause of a replacement cost of the polishing pad110and an opportunity cost caused by a downtime for a replacement of the polishing pad110.

In an implementation, if the organic polishing booster is appropriately selected, a sufficient polishing rate may be obtained without the need for inorganic polishing particles. When the inorganic polishing particles are not included in the slurry composition for the CMP process, damage to and contamination of a polishing object may be reduce or prevented, and the abrasion of the polishing pad may be reduced, thereby reducing manufacturing costs. In addition, the manufacturing costs may be further reduced in that the slurry composition itself for the CMP process may be inexpensive.

The slurry composition for the CMP process may not include a dispersion stabilizer. The slurry composition for the CMP process may not include inorganic polishing particles as described above, and a dispersion stabilizer (that may otherwise be added to obtain good dispersion of inorganic polishing particles) may be unnecessary.

pH Control Agent

In an implementation, the slurry composition for the CMP process may further include a pH control agent for controlling a pH of the composition. In an implementation, the slurry composition for the CMP process may have a pH of, e.g., about 1 to about 9. In an implementation, the slurry composition for the CMP process may have a pH of, e.g., about 2 to about 7. In an implementation, the slurry composition for the CMP process may have a pH of, e.g., about 2 to about 5.

To control a pH of the slurry composition for the CMP process as needed, an acidic solution and an alkali solution may be appropriately used. In an implementation, the pH control agent may include an acidic solution (e.g., sulfuric acid, phosphoric acid, hydrochloric acid, nitric acid, carboxylic acid, maleic acid, malonic acid, citric acid, oxalic acid, or tartaric acid) or an alkali solution (e.g., calcium hydroxide, potassium hydroxide, ammonium hydroxide, sodium hydroxide, magnesium hydroxide, triethylamine, tetra methyl ammonium hydroxide (TMAH), or ammonia). The pH control agent may be included in the slurry composition for the CMP process at such an amount that the pH of the slurry composition for the CMP process is in a desired range.

Surfactant

In an implementation, the slurry composition for the CMP process may further include a surfactant as desired. In an implementation, the surfactant may include, e.g., a non-ionic surfactant, a cationic surfactant, an anionic surfactant, or an amphoteric surfactant.

The non-ionic surfactant may include, e.g., polyoxyethylene alkylethers such as polyoxyethylene laurylether and polyoxyethylene stearylether; polyoxyethylene alkylphenylethers such as polyoxyethylene octylphenylether and polyoxyethylene nonyl phenylether; sorbitan higher fatty acid esters such as sorbitan monolaurate, sorbitan monostearate, and sorbitan trioleate; polyoxyethylene sorbitan higher fatty acid esters such as polyoxyethylene sorbitan monolaurate; polyoxyethylene higher fatty acid esters such as polyoxyethylene monolaurate and polyoxyethylene monostearate; glycerine higher fatty acid esters such as oleic acid monoglyceride and stearic acid monoglyceride; polyoxyalkylenes such as polyoxyethylene, polyoxypropylene, and polyoxybutylene, or block copolymers thereof.

The surfactant may be included in an amount of, e.g., about 0.001% by weight to about 0.5% by weight, based on the total weight of the slurry composition for the CMP process.

Leveling Agent

In an implementation, the slurry composition for the CMP process may further include a leveling agent for reducing irregularities of a polished surface as desired.

The leveling agent may be included in an amount of, e.g., about 0.1% by weight to about 1% by weight, based on the total weight of the slurry composition for the CMP process.

In an implementation, the slurry composition for the CMP process may further include an oxidizer. In an implementation, the oxidizer may include, e.g., organic peroxides such as peracetic acid, perbenzoic acid, and tert-butyl hydroperoxide; permanganic acid compounds such as potassium permanganate; dichromic acid compounds such as potassium dichromate; halogenacid compounds such as potassium iodate; nitric acid compounds such as nitric acid and iron nitrate; perhalogenic acid compounds such as perchloric acid; persulfates such as sodium persulfate, potassium persulfate, and ammonium persulfate; percarbonates such as sodium percarbonate and potassium percarbonate; urea peroxide; or heteropolyacids.

Corrosion Inhibitor

In an implementation, the slurry composition for the CMP process may further include, e.g., a corrosion inhibitor for protecting a surface to be polished from corrosion, as needed.

In an implementation, the corrosion inhibitor may include, e.g., triazole and derivatives thereof or benzene triazole and derivatives thereof. In an implementation, the triazole derivatives may include, e.g., an amino-substituted triazole compound and a bi-amino-substituted triazole compound.

The corrosion inhibitor may be included in an amount of, e.g., about 0.001% by weight to about 0.15% by weight, based on the total weight of the slurry composition for the CMP process. In an implementation, the corrosion inhibitor may be included in an amount of, e.g., about 0.0025% by weight to about 0.1% by weight or about 0.005% by weight to about 0.05% by weight.

In an implementation, when a CMP process is performed at a pH of about 4.0 and while applying a pressure of about 3 psi to a polysilicon film, the slurry composition for the CMP process may have a polishing rate of, e.g., about 1,600 Å/min to about 3,000 Å/min.

By using the slurry composition for the CMP process, according to the embodiment, product defects and manufacturing costs may be reduced, and product throughput may be increased.

Comparative Example 1

A slurry composition including ceria particles in an amount of 3% by weight, a polymer having a repeating unit of Formula 8′ and a weight-averaged molecular weight of 55,000 as an organic polymer booster in an amount of 2,000 ppm by weight (here, R1=methyl group), and DIW as a carrier was prepared. A pH of the slurry composition was adjusted to 4.0 by using nitric acid as a pH control agent.

Comparative Example 2

A slurry composition for a CMP process was prepared in the same manner as in Comparative Example 1 except that ceria particles and an organic polishing booster were omitted.

Experimental Example 1

A slurry composition for a CMP process was prepared in the same manner as in Comparative Example 1 except that ceria particles were omitted.

Polysilicon layers were polished by using the slurry compositions for the CMP processes, according to Experimental Example 1 and Comparative Examples 1 and 2. A polishing pressure was adjusted to 3 psi, rotation rates of a platen and a carrier head were adjusted to 93 rpm and 87 rpm, respectively, and a flow rate of the slurry composition for the CMP process was adjusted to 250 ml/min. Thicknesses of the polysilicon layers before and after polishing processes were measured, and polishing rates were calculated and are summarized in Table 1.

As shown in Table 1, a polishing rate of the slurry composition including inorganic polishing particles, according to Comparative Example 1, was about 10% higher than a polishing rate of the slurry composition according to Experimental Example 1, which did not include inorganic polishing particles. However, the polishing rate (2,000 Å/min) of the slurry composition according to Experimental Example 1 was also a sufficient polishing rate for an actual process.

Moreover, the slurry composition according to Comparative Example 2, which did not include an organic polishing booster, exhibited an extremely low polishing rate.

Comparative Examples 3 to 8

In each of Comparative Examples 3 to 8, a slurry composition including ceria particles in an amount of 3% by weight, a compound having a structure indicated in Table 2 as an organic polishing booster in an amount of 2,500 ppm by weight, and DIW as a carrier was prepared. A pH of the slurry composition was adjusted to 4.0 by using nitric acid as a pH control agent.

Experimental Examples 2 to 7

Slurry compositions for CMP processes were respectively prepared in the same manners as in Comparative Examples 3 to 8 except that ceria particles were omitted.

Polysilicon layers were polished by using the slurry compositions for the CMP processes, according to Experimental Examples 2 to 7 and Comparative Examples 2 to 8. A polishing pressure was adjusted to 3 psi, rotation rates of a platen and a carrier head were adjusted to 93 rpm and 87 rpm, respectively, and a flow rate of the slurry composition for the CMP process was adjusted to 250 ml/min. Thicknesses of the polysilicon layers before and after polishing processes were measured, and polishing rates were calculated and are summarized in Table 2.

Experimental Example 8

A slurry composition for a CMP process was prepared in the same manner as in Experimental Example 2 except that a pH of the slurry composition for the CMP process was controlled to be 8.5.

Thereafter, a polysilicon layer was polished by using the slurry composition for the CMP process, according to Experimental Example 8. A polishing pressure was adjusted to 3 psi, rotation rates of a platen and a carrier head were adjusted to 93 rpm and 87 rpm, respectively, and a flow rate of the slurry composition for the CMP process was adjusted to 250 ml/min. Thicknesses of the polysilicon layer before and after a polishing process were measured, and a polishing rate was calculated. As a result, a polishing rate of 1,084 Å/min was obtained.

When the polishing rate of Experimental Example 2 is compared with the polishing rate of Experimental Example 8, it may be seen that a pH of a slurry composition for a CMP process significantly affected a polishing rate thereof.

Hereinafter, a method of manufacturing a semiconductor device by using the above-described CMP process will be described.

FIGS. 2A to 2Mare cross-sectional views of stages in a method of manufacturing a semiconductor device300according to an embodiment.

Referring toFIG. 2A, an interlayer insulating film320may be formed on a substrate310(including a plurality of active regions AC), and may be patterned to expose at least portions of the plurality of active regions AC. The interlayer insulating film320may include recess portions RE exposing the active regions AC. The recess portions RE may be contact holes or trenches. In an implementation, the recess portions RE may be contact holes, or the recess portions RE may be trenches.

The substrate310may include a semiconductor (e.g., silicon (Si) or germanium (Ge)) or a compound semiconductor (e.g., silicon germanium (SiGe), silicon carbide (SiC), gallium arsenide (GaAs), indium arsenide (InAs), or indium phosphide (InP)). In an implementation, the substrate310may include a Group III-V material or a Group IV material. The Group III-V material may be a binary compound, a ternary compound, or a quaternary compound including at least one Group III atom and at least one Group V atom. The Group III-V material may be a compound including a Group III atom (e.g., In, Ga, or Al) and a Group V atom (e.g., arsenic (As), phosphorus (P), or antimony (Sb)). In an implementation, the Group III-V material may include InP, InzGa1-zAs (0≤z≤1), or AlzGa1-zAs (0≤z≤1). The binary compound may be, e.g., InP, GaAs, InAs, InSb, or GaSb. The ternary compound may be, e.g., InGaP, InGaAs, AlinAs, InGaSb, GaAsSb, or GaAsP. The Group IV material may be, e.g., silicon or germanium. In an implementation, the substrate310may have a silicon-on-insulator (SOI) structure. The substrate310may include a conductive region, e.g., a doped well or a doped structure.

The plurality of active regions AC may be defined by a plurality of device isolation regions312formed in the substrate310. The device isolation regions312may include a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or a combination thereof.

The interlayer insulating film320may include a silicon oxide film.

Referring toFIG. 2B, a barrier metal material layer322mmay be formed inside the recess portions RE and on an entire top surface of the interlayer insulating film320. The barrier metal material layer322mmay be formed using an atomic layer deposition (ALD) process, a chemical vapor deposition (CVD) process, or a physical vapor deposition (PVD) process. The barrier metal material layer322mmay include, e.g., titanium (Ti) or titanium nitride (TiN).

In an implementation, a conductive material layer324mmay be formed on an entire top surface of the barrier metal material layer322m. The conductive material layer324mmay include doped polysilicon or a metal, e.g. tungsten (W), and may be formed using a CVD process.

Referring toFIG. 2C, a CMP process may be performed on the conductive material layer324mso that the conductive material layer324mmay be defined inside the recess portions RE. In an implementation, the slurry composition for a CMP process according to an embodiment, which has been described above, may be used. In an implementation, inorganic polishing particles, such as silica, ceria, and alumina, may not be included in the slurry composition for the CMP process.

In this case, the CMP process may be performed using the barrier metal material layer322mas a polishing stop film.

Referring toFIG. 2D, a CMP process may be performed on the barrier metal material layer322m, which is exposed, so that a barrier metal layer322may be defined inside each of the contact holes and the contact holes may be completely node-separated from each other. A plurality of conductive regions324may be on the barrier metal layer322in the contact holes. To this end, a slurry composition for a CMP process according to an embodiment, which has been described above, may be used.

The CMP process ofFIG. 2Dmay be performed by using the slurry composition that does not include inorganic polishing particles, in the same manner as described with reference toFIG. 2C.

In an implementation, as illustrated inFIGS. 2C and 2Dtwo CMP processes may be respectively performed using the barrier metal material layer322mand the interlayer insulating film320as a polishing stop film. In an implementation, a single CMP process may be performed by using only the interlayer insulating film320as a polishing stop film.

In an implementation, the slurry composition for the CMP process may be controlled to have a pH of about 2 to 7. In an implementation, when a metal or polysilicon is polished as shown inFIGS. 2C and 2D, a pH of the slurry composition for the CMP process may be controlled to be an acidic pH value, e.g.,2to5.

The plurality of conductive regions324may be connected to one of the terminals of switching devices (e.g., field-effect transistors (FETs)) formed on the substrate310. The plurality of conductive regions324may include, e.g., doped polysilicon, metal, conductive metal nitride, metal silicide, or a combination thereof.

Referring toFIG. 2E, an insulating layer328may be formed to cover the interlayer insulating film320and the plurality of conductive regions324. The insulating layer328may be used as an etch stop layer.

The insulating layer328may include an insulating material having an etch selectivity with respect to the interlayer insulating film320and a mold film (refer to330inFIG. 2F) that will be formed in a subsequent process. In an implementation, the insulating layer328may include silicon nitride, silicon oxynitride, or a combination thereof.

In an implementation, the insulating layer328may be formed to a thickness of, e.g., about 100 Å to about 600 Å.

Referring toFIG. 2F, the mold film330may be formed on the insulating layer328.

In an implementation, the mold film330may include an oxide film. In an implementation, the mold film330may include an oxide film, such as a borophosphosilicate glass (BPSG) film, a phosphosilicate glass (PSG) film, an undoped silicate glass (USG) film, a spin on dielectric (SOD) film, or an oxide film formed by using a high-density-plasma chemical vapor deposition (HDP CVD) process. The mold film330may be formed using a thermal CVD process or a plasma CVD process. In an implementation, the mold film330may be formed to a thickness of, e.g., about 1,000 Å to about 20,000 Å.

In an implementation, the mold film330may include a support film. The support film may include a material having an etch selectivity with respect to the mold film330and have a thickness of about 50 Å to about 3,000 Å. When the mold film330is subsequently removed by using a LAL lift-off process in an etching atmosphere of, e.g., ammonium fluoride (NH4F), hydrofluoric acid (HF), and water, the support film may include a material having a relatively low etch rate with respect to LAL. In an implementation, the support film may include silicon nitride, silicon carbonitride, tantalum oxide, titanium oxide, or a combination thereof.

Referring toFIG. 2G, a sacrificial film342and a mask pattern344may be sequentially formed on the mold film330.

The sacrificial film342may include an oxide film, such as a BPSG film, a PSG film, an USG film, an SOD film, or an oxide film formed by using an HDP CVD process. The sacrificial film342may have a thickness of about 500 Å to about 2,000 Å. The sacrificial film342may help protect the support film included in the mold film330.

The mask pattern344may include an oxide film, a nitride film, a polysilicon film, a photoresist film, or a combination thereof. A region where a lower electrode of a capacitor will be formed may be defined by the mask pattern344.

Referring toFIG. 2H, the sacrificial film342and the mold film330may be dry etched by using the mask pattern344as an etch mask and using the insulating layer328as an etch stop layer, thereby forming a sacrificial pattern342P and a mold pattern330P to define a plurality of holes H1.

In this case, the insulating layer328may also be etched due to excessive etching, thereby forming an insulating pattern328P to expose a plurality of conductive regions324.

Referring toFIG. 2I, the mask pattern344may be removed from the resultant structure ofFIG. 2H. Thereafter, a conductive film350for forming a lower electrode may be formed to cover an inner sidewall of each of the plurality of holes H1, an exposed surface of the insulating pattern328P, surfaces of the plurality of conductive regions324respectively exposed inside the plurality of holes H1, and an exposed surface of the sacrificial pattern342P.

The conductive film350for forming the lower electrode may be conformally formed on the inner sidewall of each of the plurality of holes H1to leave a partial inner space of each of the plurality of holes H1.

The conductive film350for forming the lower electrode may be formed by using a CVD process, a metal organic CVD (MOCVD) process, or an ALD process. In an implementation, the conductive film350for forming the lower electrode may be formed to a thickness of, e.g., about 1 nm to about 100 nm. Thereafter, a sacrificial film may be further formed to fill recess portions defined by the conductive film350for forming the lower electrode. The sacrificial film may cover a top surface of the conductive film350for forming the lower electrode.

Referring toFIG. 2J, an upper portion of the conductive film350for forming the lower electrode may be partially removed so that the conductive film350for forming the lower electrode may be separated into a plurality of lower electrodes LE.

To form the plurality of lower electrodes LE, portions of the upper portion of the conductive film350for forming the lower electrode and the sacrificial pattern342P (refer toFIG. 2I) may be removed by using an etchback process or a CMP process so that a top surface of the mold pattern330P is exposed.

The plurality of lower electrodes LE may pass through the insulating pattern328P and be connected to the conductive regions324.

Referring toFIG. 2K, the mold pattern330P may be removed to expose outer wall surfaces of the plurality of lower electrodes LE having cylindrical shapes.

The mold pattern330P may be removed by a lift-off process using LAL or hydrofluoric acid.

Referring toFIG. 2L, a dielectric film360may be formed on the plurality of lower electrodes LE.

The dielectric film360may be formed to conformally cover exposed surfaces of the plurality of lower electrodes LE.

The dielectric film360may be formed using an ALD process.

The dielectric film360may include an oxide, a metal oxide, a nitride, or a combination thereof. In some embodiments, the dielectric film360may include a ZrO2film. In an implementation, the dielectric film360may include a single ZrO2layer or a multilayered structure including a combination of at least one ZrO2film and at least one Al2O3film.

In an implementation, the dielectric film360may have a thickness of, e.g., about 50 Å to about 150 Å.

Referring toFIG. 2M, an upper electrode UE may be formed on the dielectric film360.

A capacitor370may be configured by the lower electrode LE, the dielectric film360, and the upper electrode UE.

The upper electrode UE may include a doped semiconductor, a conductive metal nitride, a metal, a metal silicide, a conductive oxide, or a combination thereof. In an implementation, the upper electrode UE may include TiN, TiAlN, TaN, TaAlN, W, WN, Ru, RuO2, SrRuO3, Ir, IrO2, Pt, PtO, SrRuO3(SRO), (Ba,Sr)RuO3(BSRO), CaRuO3(CRO), (La,Sr)CoO3(LSCo), or a combination thereof.

The upper electrode UE may be formed by using a CVD process, an MOCVD process, a physical vapor deposition (PVD) process, or an ALD process.

In an implementation, the method of manufacturing the semiconductor device300may include the process of forming the dielectric film360to cover the surfaces of the lower electrodes LE having cylindrical shapes. In an implementation, pillar-type lower electrodes having no inner spaces may be formed instead of the lower electrodes LE having cylindrical shapes. The dielectric film360may be formed on the pillar-type lower electrodes.

In the method of manufacturing the semiconductor device300according to the embodiment as described with reference toFIGS. 2A to 2M, a CMP process may be performed by using the slurry composition for the CMP process according to the embodiment to form the barrier metal layer322and the conductive regions324. In an implementation, a CMP process using the slurry composition for the CMP process according to the embodiments may be applied to methods of manufacturing other semiconductor devices.

By way of summation and review, some polishing agents may cause product defects depending on polishing conditions.

One or more embodiments may provide a slurry composition for a CMP process, which may help reduce product defects, incur low manufacturing costs, and increase product throughput.

One or more embodiments may provide a slurry composition for a polysilicon polishing process, which may help reduce product defects, incur low manufacturing costs, and increase product throughput.