TWI675099B - Method for forming semiconductor device - Google Patents

Abstract

In some embodiments, a method for manufacturing a semiconductor device is provided, including: forming a material layer on a semiconductor substrate; forming an opening in the material layer; depositing a metal layer in the opening and extending onto the material layer; and A part of the metal layer of chemical mechanical polishing, wherein one of the polishing liquids used in chemical mechanical polishing includes: an organic base having a lone pair of electrons; and an oxidant.

Description

Manufacturing method of semiconductor device

Embodiments of the present invention relate to a method for manufacturing a semiconductor device, and more particularly, to a method for manufacturing a semiconductor device using a metal chemical mechanical polishing process.

The semiconductor integrated circuits (IC) industry has experienced rapid development. Advances in integrated circuit materials and design technology have made integrated circuits produced in each generation smaller and more complex than previously produced integrated circuits. In the development of integrated circuits, the functional density (that is, the number of interconnect devices in each chip area) has generally increased, and the geometric size (that is, the smallest component or circuit that can be created in the process) ) Is generally down. This miniaturization process usually provides many benefits by increasing production efficiency and reducing related expenses. However, such miniaturization has also increased the complexity of integrated circuit processing and manufacturing, and in order to achieve such progress, the same progress must be made in integrated circuit processing and manufacturing.

In the manufacturing process of integrated circuits, chemical mechanical polishing (CMP) is a widely used process that can provide comprehensive planarization of the wafer surface. For example, in a semiconductor manufacturing process, a chemical mechanical polishing process may be used to planarize, for example, a dielectric layer, a metal layer, or a semiconductor layer.

Traditionally, metal chemical mechanical polishing (metal CMP) is used The polishing liquid uses inorganic alkali as the pH adjusting agent. However, during the metal chemical mechanical polishing process, the metal being ground will become ionic and dissolve in the polishing liquid. These metal ions are easily reacted with the hydroxyl group (OH group) generated by the inorganic base to form insoluble Metal oxide particles (hereinafter referred to as metal particles), for example, copper oxide, cobalt oxide, and the like. During or after the metal chemical mechanical polishing process, these metal particles will be re-deposited on the surface of the integrated circuit, resulting in a decrease in the yield of the product.

Therefore, in order to improve the yield of the product, the metal redeposition phenomenon on the surface of the integrated circuit during or after the metal chemical mechanical polishing process must be reduced or avoided.

According to some embodiments, a method for manufacturing a semiconductor device is provided, including: forming a material layer on a semiconductor substrate; forming an opening in the material layer; depositing a metal layer in the opening and extending onto the material layer; and chemically A portion of the metal layer is mechanically ground. One of the polishing liquids used in chemical mechanical grinding includes: an organic base having a lone pair of electrons; and an oxidant.

According to some embodiments, a method for manufacturing a semiconductor device is provided, including: forming a dielectric layer on a semiconductor substrate; forming an opening through the dielectric layer to expose the semiconductor substrate; and depositing a barrier layer in the opening to neutralize the dielectric On the electrical layer; depositing a metal layer in the opening and extending to the barrier layer; and chemically and mechanically polishing the metal layer until the barrier layer is exposed, one of the polishing fluids used in chemical mechanical polishing includes: alkyl ammonium, ammonia (ammonia), or a combination thereof; and an oxidant. Among them, an upper surface of the chemical mechanically polished metal layer is flush with an upper surface of one of the dielectric layers.

According to some embodiments, a method for manufacturing a semiconductor device is provided, comprising: depositing a metal layer on a semiconductor substrate; chemically mechanically polishing a portion of the metal layer; wherein a polishing liquid used in chemical mechanical polishing includes an oxidant and an organic base . Among them, the organic base includes a primary amine compound having the following formula (I), a secondary amine compound having the following formula (II), a tertiary amine compound having the following formula (III), and a quaternary ammonium having the following formula (IV) A compound, or a combination of the foregoing;

Wherein, R ¹ to R ¹⁰ may be the same or different, and each independently includes an unsubstituted or substituted C ₁ -C ₆ alkyl group and a C ₆ -C ₁₄ aromatic group, wherein the substituents on the alkyl group include: C ₁ -C ₈ alkoxy, C ₁ -C ₈ alkyl, nitro, halogen atom, carboxyl, or hydroxyl, wherein the substituent on the aromatic group includes: C ₁ -C ₈ alkoxy, carboxyl, alkoxycarbonyl, C ₁ -C ₈ haloalkyl of, C ₅ -C ₈ cycloalkyl, or C ₁ -C ₈ alkylthio. Wherein, the weight% of the organic base is greater than 50% by weight, based on the total weight of the organic base and the optionally added inorganic base in the polishing liquid.

20a, 20b‧‧‧semiconductor device

100, 300‧‧‧ methods

102, 104, 106, 108, 302, 304, 306, 308, 310‧‧‧ steps

200‧‧‧ semiconductor substrate

202‧‧‧material layer / dielectric layer

204‧‧‧ opening

206‧‧‧metal layer

208‧‧‧Metal Structure

405‧‧‧Barrier

500‧‧‧ chemical mechanical grinding tools

502‧‧‧rotating platform

504‧‧‧ Abrasive pad

506‧‧‧ substrate holding device

508‧‧‧Grinding fluid supplier

510‧‧‧ grinding fluid

512‧‧‧rotating arm

514‧‧‧Nozzle

520‧‧‧center shaft

530‧‧‧ Abrasive Pad Adjuster

In order to make the above and other objects, features, and advantages of the present invention more comprehensible, the following describes the preferred embodiments in detail with the accompanying drawings, as follows:

FIG. 1 is a flowchart illustrating a method for manufacturing a semiconductor device according to some embodiments.

2A to 2D are cross-sectional views showing semiconductor devices at various manufacturing stages according to some embodiments.

FIG. 3 is a flowchart illustrating a method of manufacturing a semiconductor device according to some embodiments.

4A to 4E are cross-sectional views showing semiconductor devices at various manufacturing stages according to some embodiments.

FIG. 5 is a schematic diagram showing a chemical mechanical polishing apparatus according to some embodiments.

Examples of specific elements and their arrangements are described below to simplify the present invention. Of course these are just examples and should not be used to limit the scope of the invention. For example, when it is mentioned in the description that the first element is formed on the second element, it may include Including the embodiment in which the first element is in direct contact with the second element, it may also include the embodiment in which other elements are formed between the two without direct contact. In addition, repeated reference numerals and / or symbols may be used in different embodiments. These repetitions are only for simply and clearly describing the present invention, and do not represent a specific relationship between the different embodiments and / or structures discussed.

In addition, space-related terms such as "below", "below", "lower", "above", "higher", and similar terms may be used. These relationships Words are used to facilitate the description of the relationship between one or more elements or features and other elements or features in the drawings. These spatial relations include different positions of the device in use or operation, as well as the positions described in the drawings. The device may be turned to different orientations (rotated 90 degrees or other orientations), and the spatially related adjectives used therein can be interpreted the same way.

The description of the present invention provides different embodiments to explain the technical features of the different embodiments. For example, "some embodiments" referred to throughout the specification means that a particular feature, structure, or characteristic described in an embodiment is included in at least one embodiment. Therefore, the phrases “in some embodiments” appearing in different places throughout the specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Further, for the terms "including", "having", "having", "wherein" or the foregoing transformations used herein, these semantics are similar to the terms "including" to include corresponding features.

The embodiments of the present invention are best read in conjunction with the illustrations and detailed descriptions for easy understanding. It is emphasized that, in accordance with industry standard practice, component symbols will not be drawn to scale. For ease of explanation and discussion, the dimensions of each icon may be Intentional zoom in or zoom out.

In order to solve the product yield reduction caused by the metal redeposition phenomenon on the surface of the integrated circuit, the metal redeposition on the surface of the integrated circuit can be removed after the chemical mechanical polishing process. However, when metal redeposition (metal particles) is removed, it is easy to cause unnecessary metal corrosion because the removal range cannot be accurately grasped.

An embodiment of the present invention provides a method for manufacturing a semiconductor device. The embodiment of the present invention improves the metal chemical mechanical polishing (metal CMP) process, and provides a slurry solution for chemical mechanical polishing of a metal layer. In this polishing liquid, specific organic bases partially or completely replace the inorganic bases used in traditional metal chemical mechanical polishing liquids to reduce or prevent metal ions from reacting with OH groups generated by inorganic bases to form metal particles. . This can solve the problem of yield reduction caused by the metal redeposition phenomenon on the surface of the integrated circuit.

FIG. 1 is a flowchart illustrating a method 100 for manufacturing a semiconductor device according to some embodiments. The method 100 is described below with reference to FIGS. 2A to 2D, and FIGS. 2A to 2D are cross-sectional views of an example semiconductor device at each process stage.

First, in some embodiments, step 102 of the method 100 is performed to form a material layer 202 on a semiconductor substrate 200, as shown in FIG. 2A. In some embodiments, the semiconductor substrate 200 may be a block semiconductor substrate, such as a semiconductor wafer. For example, the semiconductor substrate 200 may be a silicon wafer. In some embodiments, the semiconductor substrate 200 may include silicon or other elemental semiconductor materials, such as germanium. In some embodiments, the semiconductor substrate 200 may include a sapphire substrate, a silicon substrate, or a silicon carbide substrate. For example, the semiconductor substrate 200 may be selected from It is formed of at least one semiconductor material in the group consisting of Si, Ge, SiGe, GaP, GaAs, GaAsP, GaInP, SiC, SiGeC, InAs, and InP. In some embodiments, the semiconductor substrate 200 may also include a silicon on insulator (SOI). A silicon-on-insulator (SOI) substrate can be formed using an oxygen implant isolation (SIMOX) process, a wafer bonding process, other applicable methods, or a combination of the foregoing. In some embodiments, the semiconductor substrate 200 may also be composed of multiple layers of materials, such as: Si / SiGe, Si / SiC.

In some embodiments, the material layer 202 may include a dielectric layer, a metal layer, or a semiconductor layer. In some embodiments, the material layer 202 may be a dielectric layer. The dielectric layer may be an inter-metal dielectric (IMD) layer or an inter-layer dielectric (ILD) layer, which may be formed of a dielectric material. For example, in some embodiments, the dielectric layer may be formed of an oxide, such as silicon dioxide or a high density plasma oxide. In some embodiments, the dielectric layer may be made of borophosphosilicate glass (BPSG), spin on glass (SOG), undoped silicate glass (USG), Fluorinated silicate glass (FSG), similar materials, or a combination of the foregoing. In some embodiments, a low-temperature plasma-enhanced atomic layer deposition (PEALD) process or a plasma-enhanced chemical vapor deposition (PECVD) process may be used for deposition. Dielectric layer.

Referring to FIG. 2B, in some embodiments, step 104 of the method 100 is performed to form an opening 204 in the material layer 202. In some embodiments, the openings 204 may be formed using, for example, one or more lithography and etching processes.

Referring to FIG. 2C, in some embodiments, step 106 of the method 100 is performed, a metal layer 206 is deposited in the opening 204 and extends onto the material layer 202 to form a semiconductor device 20a. In some embodiments, the metal layer 206 may be formed by, for example, chemical vapor deposition (CVD), physical vapor deposition (PVD), other applicable processes, or a combination of the foregoing processes. The material is filled in the opening 204 and deposited on the material layer 202 on the semiconductor substrate 200.

In some embodiments, the material of the metal layer 206 may include: a transition metal, a metal, or a mixture thereof. In some embodiments, examples of transition metals include: scandium (Sc), yttrium (Y), lanthanum (La), samarium (Ac), titanium (Ti), zirconium (Zr), hafnium (Hf), furnace (Rf ), Cerium (Ce), thorium (Th), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), thorium (Tc ), Osmium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt ), Copper (Cu), silver (Ag), gold (Au), zinc (Zn), cadmium (Cd), or a combination thereof. Examples of metals include: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), rubidium (Fr), beryllium (Be), magnesium (Mg), calcium (Ca), Strontium (Sr), Barium (Ba), Ra (Ra), Aluminum (Al), Gallium (Ga), Indium (In), Thorium (Tl), Germanium (Ge), Tin (Sn), Lead (Pb), Antimony (Sb), bismuth (Bi), thorium (Po), or a combination thereof.

Referring to FIG. 2D, in some embodiments, step 108 of the method 100 is performed to chemically and mechanically polish a portion of the metal layer 206. In some embodiments, the metal layer 206 may be subjected to a chemical mechanical polishing process until an upper surface of the material layer 202 is exposed.

As shown in FIG. 2D, in some embodiments, the metal layer 206 subjected to chemical mechanical polishing forms a metal structure 208. In some embodiments, an upper surface of the metal structure 208 is flush with an upper surface of one of the material layers 202. In some embodiments, the metal structure 208 may be, for example, a contact or a metal line.

In some embodiments, one of the polishing fluids used in chemical mechanical polishing includes an organic base having a lone pair of electrons and an oxidant. In some embodiments, an organic base can be used as a pH adjuster in the polishing liquid.

In some embodiments, the organic base having a lone pair of electrons may include an alkylamine, ammonia, or a combination thereof. In some embodiments, the alkyl amine may include: primary (1 °) amines, secondary (2 °) amines, tertiary amines Compounds, quaternary (4 °) ammonium compounds, or combinations thereof.

In some embodiments, the primary amine compound may have the following formula (I):

Wherein, R ¹ may include an unsubstituted or substituted alkyl group or aryl group. In some embodiments, specific examples may include C ₁ -C ₆ alkyl groups, C ₆ -C ₁₄ aromatic groups, and substituted derivatives. In some embodiments, examples of the substituent on the alkyl group may include: a C ₁ -C ₈ alkoxy group, a C ₁ -C ₈ alkyl group, a nitro group, A halogen atom, a carboxyl group, and a hydroxyl group. In some embodiments, examples of the substituent on the aromatic group may include: C ₁ -C ₈ alkoxy, carboxyl, alkoxycarbonyl group, C ₁ -C ₈ haloalkyl group, C ₅ -C ₈ cycloalkyl group and C ₁ -C ₈ alkylthio group.

For example, in some embodiments, the primary amine compound may be, for example, methylamine, ethylamine, cyclohexylamine, 2-aminoethanol (MEA), or the foregoing combination.

In some embodiments, the secondary amine compound may have the following formula (II):

Wherein, R ² and R ³ may be the same or different, and each may independently include an unsubstituted or substituted alkyl or aromatic group. In some embodiments, specific examples may include C ₁ -C ₆ alkyl groups, C ₆ -C ₁₄ aromatic groups, and substituted derivatives. In some embodiments, examples of the substituent on the alkyl group may include a C ₁ -C ₈ alkoxy group, a C ₁ -C ₈ alkyl group, a nitro group, a halogen atom, a carboxyl group, and a hydroxyl group. In some embodiments, examples of the substituent on the aromatic group may include: C ₁ -C ₈ alkoxy, carboxyl, alkoxycarbonyl, C ₁ -C ₈ haloalkyl, C ₅ -C ₈ cycloalkane And C ₁ -C ₈ alkylthio.

For example, in some embodiments, the secondary amine compound may be dimethylamine, diethylamine, methylethylamine, or a combination thereof.

In some embodiments, the tertiary amine compound may have the following formula (III):

Wherein, R ⁴ , R ⁵ , and R ⁶ may be the same or different, and each may independently include an unsubstituted or substituted alkyl or aromatic group. In some embodiments, specific examples may include C ₁ -C ₆ alkyl groups, C ₆ -C ₁₄ aromatic groups, and substituted derivatives. In some embodiments, examples of the substituent on the alkyl group may include a C ₁ -C ₈ alkoxy group, a C ₁ -C ₈ alkyl group, a nitro group, a halogen atom, a carboxyl group, and a hydroxyl group. In some embodiments, examples of the substituent on the aromatic group may include: C ₁ -C ₈ alkoxy, carboxyl, alkoxycarbonyl, C ₁ -C ₈ haloalkyl, C ₅ -C ₈ cycloalkane And C ₁ -C ₈ alkylthio.

For example, in some embodiments, the tertiary amine compound may be trimethylamine (TMA), triethylamine (TEA), N-methyl-N-ethylaniline (N-methyl- N-ethylaniline), or a combination thereof.

In some embodiments, the quaternary ammonium compound may have the following chemical formula:

Among them, R ⁷ , R ⁸ , R ⁹ , and R ¹⁰ may be the same or different, and each may independently include an unsubstituted or substituted alkyl or aromatic group. In some embodiments, specific examples may include C ₁ -C ₆ alkyl groups, C ₆ -C ₁₄ aromatic groups, and substituted derivatives. In some embodiments, examples of the substituent on the alkyl group may include a C ₁ -C ₈ alkoxy group, a C ₁ -C ₈ alkyl group, a nitro group, a halogen atom, a carboxyl group, and a hydroxyl group. In some embodiments, examples of the substituent on the aromatic group may include: C ₁ -C ₈ alkoxy, carboxyl, alkoxycarbonyl, C ₁ -C ₈ haloalkyl, C ₅ -C ₈ cycloalkane And C ₁ -C ₈ alkylthio.

For example, in some embodiments, the quaternary ammonium compound may be tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (tetrapropylammonium hydroxide; TPAH), tetrabutylammonium hydroxide (TBAH), or a combination thereof.

It should be noted that the above-mentioned primary amine compounds, secondary amine compounds, and tertiary amine compounds have a pair of lone pairs of electrons in addition to the three groups, so using these amine compounds as organic bases can attract Metal ions generated during chemical mechanical grinding. However, although the above-mentioned quaternary ammonium compound does not have a lone pair of electrons, it can be understood according to the common knowledge in the technical field that the quaternary ammonium compound and the tertiary amine compound will show a dynamic equilibrium during the actual reaction, so The quaternary ammonium compound also has the ability to attract metal ions, and is suitable for use as an organic base in the embodiments of the present invention.

In addition, it is worth mentioning that after the inorganic base used in the traditional metal chemical mechanical polishing liquid dissociates OH groups, it easily reacts with metal ions generated during the chemical mechanical polishing to form metal particle deposition. However, in the embodiment of the present invention, after the organic base having a lone pair of electrons attracts metal ions generated during chemical mechanical polishing, the alkyl ammonium ion or ammonium ion formed is soluble in the polishing solution and It is removed during a subsequent chemical mechanical polishing (CMP) cleaning step, so metal ions are not deposited as insoluble metal particles. Such a result is beneficial to reduce or avoid metal redeposition on the surface of the integrated circuit during or after the metal chemical mechanical polishing process in the past.

In some embodiments, the polishing liquid may include only the organic base as the pH adjusting agent. In some embodiments, when the polishing liquid includes only the above-mentioned organic base, it is equivalent to completely replace the inorganic base used in the conventional metal chemical mechanical polishing liquid with the organic base disclosed in the embodiment of the present invention. At this time, there is no OH group generated by the inorganic base in the polishing liquid, and all metal ions generated during metal chemical mechanical polishing will react with the organic base. Therefore, the effect of metal particle free formation can be achieved during or after metal chemical mechanical polishing, so no metal is deposited on the surface of the integrated circuit.

In some embodiments, the polishing liquid may further include an inorganic base. In some embodiments, the inorganic base may include, but is not limited to, lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, ammonium hydroxide, or a combination thereof.

In some embodiments, when the polishing liquid includes the organic base described above, In the case of inorganic base, it is equivalent to partially replacing the inorganic base used in the conventional metal chemical mechanical polishing liquid with the organic base disclosed in the embodiment of the present invention. At this time, although the OH group generated by the inorganic base still exists in the polishing solution, because part of the metal ions that can react with the OH group has been attracted by the organic base having a lone pair of electrons to form an alkyl ammonium ion or ammonium Root ions, so when the reactants (ie, metal ions) forming metal particles are reduced, the formation of metal particles is also reduced. Therefore, at this time, the effect of reducing the formation of metal particles can also be achieved during or after metal chemical mechanical polishing, thereby reducing the redeposition of metal on the surface of the integrated circuit.

In some embodiments, the concentration of the organic base in the polishing liquid may be greater than 10 ppm and less than or equal to 10,000 ppm. For example, in some embodiments, the concentration of the organic base in the polishing liquid may be, for example, greater than 1000 ppm and less than or equal to 10,000 ppm. In some embodiments, the concentration of the organic base in the polishing solution is about 10 ppm. At this time, the organic base is equivalent to replacing 50% by weight of the inorganic base as the pH adjusting agent. In some embodiments, the concentration of the organic base in the polishing solution is about 10000 ppm, and at this time, it is equivalent to replace 100% by weight of the inorganic base with the organic base as the pH adjusting agent.

In the embodiment of the present invention, the more the organic base content of the polishing liquid, that is, the higher the ratio of replacing the inorganic base with the organic base, the better the effect of suppressing metal redeposition. According to some embodiments, compared to using only an inorganic base as a pH adjuster, when the organic base is used instead of 50% by weight of the inorganic base as a pH adjuster, the number of metal particles detected is reduced to the original number of metal particles About 40%. In some embodiments, compared to using only an inorganic base as a pH adjuster, when 100% by weight of the inorganic base is used as a pH adjuster, the metal particles are not detected. In some embodiments, 100% by weight of Organic base is used as a pH adjuster.

Although the embodiment of the present invention lists several specific organic base contents as examples, those with ordinary knowledge in the technical field can adjust the ratio of the organic base and the inorganic base according to actual needs, for example, for different metal layer materials, or It is a different semiconductor device system, etc., with an appropriate proportion of organic base to partially or completely replace the inorganic base in the traditional metal chemical mechanical polishing liquid as a pH adjuster to achieve the effect of reducing the number of metal particles. In some embodiments, the polishing liquid disclosed in the embodiments of the present invention can reduce or avoid the phenomenon of metal redeposition on the surface of the integrated circuit as long as the organic base is present, thereby improving the yield of the product.

In some embodiments, the polishing liquid may further include an acid. In some embodiments, the acid may be an acid commonly used in the technical field, such as inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, boric acid, carbonic acid, hypophosphorous acid, phosphorous acid, and phosphoric acid, or citric acid, formic acid, and the like. Organic acids such as acetic acid, propionic acid, benzoic acid, benzoic acid, salicylic acid, glyceric acid, oxalic acid, malonic acid, succinic acid, maleic acid, phthalic acid, malic acid, tartaric acid, lactic acid, or a combination thereof.

In some embodiments, when the polishing liquid includes a base and an acid as the pH adjusting agent, the acid may be the organic acid, the inorganic acid, or a mixture thereof. In some embodiments, combining the appropriate types and proportions of acids and bases can make the polishing liquid into a buffer solution, so that the pH value of the polishing liquid is stable and has a specific range.

In some embodiments, those skilled in the art can appropriately adjust the pH of the polishing liquid according to different metal layer materials. For example, in some embodiments, when the object for chemical mechanical polishing is a tungsten metal layer At that time, the pH of the polishing liquid was adjusted to less than 7. In some embodiments, when the subject of the chemical mechanical polishing is a copper metal layer, the pH of the polishing liquid is adjusted to be greater than 7. In some embodiments, the pH of the polishing liquid may be between about 1 and about 10, for example between about 1 and about 9.

In some embodiments, the oxidant used in the polishing liquid may include peroxide, permanganate, persulfate, monopersulfate, or a combination thereof. For example, the oxidant may include, but is not limited to, hydrogen peroxide, benzoyl peroxide, peracetic acid, di-t-butyl peroxide, di-t-butyl peroxide, Sodium peroxide, potassium permanganate, potassium peroxydisulfate, ammonium peroxydisulfate, sodium peroxydisulfate, potassium peroxymonosulfate, nitric acid Iron, potassium iodate, or a combination of the foregoing. In some embodiments, hydrogen peroxide is used as the oxidant.

In some embodiments, the polishing liquid disclosed in the embodiments of the present invention further includes a solvent. In some embodiments, the solvent used may include water, such as deionized water or distilled water.

In some embodiments, the polishing liquid disclosed in the embodiments of the present invention may further include other additives having specific functions. In some embodiments, the additives may include, but are not limited to, a chelating agent, a dispersant, a surfactant, a bacteriostatic agent, or a combination thereof.

In some embodiments, the polishing liquid used in chemical mechanical polishing may further include: an abrasive particle. In some embodiments, the material of the abrasive particles may include, but is not limited to: silicon oxide, oxygen Aluminum oxide, titanium oxide, cerium oxide, zirconium oxide, silicon carbide, silicon nitride, or a combination thereof.

In some embodiments, the abrasive particles themselves may have different electrical properties, such as: positively charged, negatively charged, or uncharged. Those with ordinary knowledge in the technical field can select abrasive particles with suitable electrical properties according to the actual situation. As long as the abrasive particles do not aggregate with the components in the slurry composition, they can be used in the embodiments of the present invention.

In some embodiments, when the disclosed polishing fluid includes abrasive particles, the polishing fluid and the abrasive particles can be planarized by chemical and mechanical forces, respectively. In some embodiments, when the disclosed polishing liquid does not include polishing particles, the polishing liquid is simply planarized by chemical force. However, since it also has an organic base component, whether the grinding fluid disclosed in the embodiments of the present invention includes grinding particles or not, the metal chemical mechanical grinding process can be used to reduce or avoid the generation of metal on the surface of the integrated circuit. The effect of deposition.

The metal chemical mechanical polishing process described in the embodiment of the present invention may include a chemical mechanical polishing process performed on different metal layers in each process stage of the semiconductor device. Similarly, the polishing liquid disclosed in the embodiment of the present invention can be applied to the chemical mechanical polishing process of various metal layers.

FIG. 3 is a flowchart illustrating a method 300 for manufacturing a semiconductor device according to some embodiments. The method 300 is described below with reference to FIGS. 4A to 4E, and FIGS. 4A to 4E are cross-sectional views of an example semiconductor device at various process stages.

First, in some embodiments, step 302 of method 300 is performed to form a dielectric layer 202 on a semiconductor substrate 200, as shown in FIG. 4A. half For the material of the conductive substrate 200, reference may be made to the relevant paragraphs in the foregoing description, and the description is not repeated here.

In some embodiments, the dielectric layer 202 may be an intermetal dielectric (IMD) layer or an interlayer dielectric (ILD) layer, which may be formed of a dielectric material. For example, in some embodiments, the dielectric layer 202 may be formed of an oxide, such as silicon dioxide or a high-density plasma oxide. In some embodiments, the dielectric layer 202 may be made of borophosphosilicate glass (BPSG), spin-on-glass (SOG), undoped silicate glass (USG), fluorinated silicate glass (FSG), It is formed of similar materials, or a combination of the foregoing. In some embodiments, the dielectric layer 202 may be deposited using a low temperature plasma enhanced atomic layer deposition (PEALD) process or a plasma enhanced chemical vapor deposition (PECVD) process.

Referring to FIG. 4B, in some embodiments, step 304 of the method 300 is performed to form an opening 204 through the dielectric layer 202 to expose the semiconductor substrate 200. In some embodiments, the openings 204 may be formed using, for example, one or more lithography and etching processes.

Referring to FIG. 4C, in some embodiments, step 306 of method 300 is performed, and a barrier layer 405 is deposited in the opening 204 and on the dielectric layer 202. In some embodiments, the barrier layer 405 may be composed of a metal-containing material. The metal-containing material may include titanium nitride, tantalum nitride, other suitable materials, or a combination of the foregoing. In some embodiments, the barrier layer 405 may include multiple layers. In some embodiments, the barrier layer 405 may be formed by an atomic layer deposition (ALD) process, a physical vapor deposition (PVD) process, an electroplating process, an electroless plating process, a chemical vapor deposition (CVD) process, or other applicable Process, or a combination of the foregoing.

Referring to FIG. 4D, in some embodiments, step 300 is performed. In step 308, a metal layer 206 is deposited in the opening 204 and extends onto the barrier layer 405 to form a semiconductor device 20b. In some embodiments, the metal layer 206 may be filled in the opening 204 and deposited on the semiconductor by using, for example, chemical vapor deposition (CVD), physical vapor deposition (PVD), other applicable processes, or a combination of the foregoing processes. On the substrate 200 and the barrier layer 405 on the dielectric layer 202.

In some embodiments, the material of the metal layer 206 may refer to the relevant paragraphs in the foregoing description, and is not repeated here.

Referring to FIG. 4E, in some embodiments, step 310 of the method 300 is performed, and a portion of the metal layer 206 is chemically and mechanically polished until the barrier layer 405 is exposed. In some embodiments, the metal layer 206 may be subjected to a chemical mechanical polishing process until an upper surface of the barrier layer 405 is exposed.

As shown in FIG. 4E, in some embodiments, the metal layer 206 subjected to chemical mechanical polishing forms a metal structure 208. In some embodiments, an upper surface of the metal structure 208 is flush with an upper surface of one of the barrier layers 405. In some embodiments, the metal structure 208 may be, for example, a contact or a metal line.

In some embodiments, one of the polishing fluids used in chemical mechanical polishing includes: alkylamine, ammonia, or a combination thereof; and an oxidant. In the polishing liquid, an alkylamine, ammonia, or a combination thereof can be used as a pH adjusting agent. For details about the alkylamine, please refer to the related paragraphs in this specification, and the details will not be repeated here. In addition, regarding the polishing liquid used in chemical mechanical polishing, please refer to the relevant paragraphs in the foregoing description of the description, and will not be repeated here.

In some embodiments, step 310 of method 300 may further include: providing the polishing liquid to an abrasive surface on a polishing pad; and rotating the polishing pad and bringing the metal layer into contact with the polishing surface to remove a portion of the metal layer until Exposed Out of the barrier layer. Hereinafter, the process steps of performing chemical mechanical polishing on the metal layer by using the polishing liquid disclosed in the embodiment of the present invention will be described with reference to FIG. 5.

FIG. 5 is a schematic diagram showing a chemical mechanical polishing apparatus 500 according to some embodiments.

As shown in FIG. 5, in some embodiments, the chemical mechanical polishing apparatus 500 may include a rotating platform 502, a polishing pad 504, a substrate holding device 506, and a polishing liquid supplier 508. The polishing pad 504 is fixed on the rotating platform 502 and is connected to the rotating platform 502. The polishing pad 504 is configured to be driven by the rotating platform 502 to rotate synchronously around the central rotation axis 520. The substrate holding device 506 is disposed above the polishing pad 504 and is configured to hold a semiconductor device 20 a in a direction parallel to the central rotation axis 520. The polishing liquid supplier 508 has a liquid outlet located above the polishing pad 504 and configured to provide a polishing liquid 510 onto the polishing pad 504.

In some embodiments, during the grinding process, the substrate holding device 506 may also drive the semiconductor device 20a thereon to rotate. The substrate holding device 506 is used to house the semiconductor device 20a upside down, so that the top surface of the semiconductor device 20a faces the rotating polishing pad 504. In some embodiments, the semiconductor device 20a is a device as shown in FIG. 2C. In some embodiments, the semiconductor device 20a may also be replaced with a semiconductor device 20b as shown in FIG. 4D. Each element in the semiconductor devices 20a, 20b, its material, and forming method can refer to the related paragraphs in this specification, and will not be repeated here.

During the chemical mechanical polishing, the polishing liquid supplier 508 can provide the polishing liquid 510 to one of the polishing surfaces on the polishing pad 504. In some embodiments, the polishing liquid supplier 508 is connected to a tank or a reservoir containing the polishing liquid 510. Register (not shown). In some embodiments, the polishing liquid supplier 508 may include a rotating arm 512 and a nozzle 514 (for example, as the aforementioned liquid outlet). The nozzle 514 is disposed at one end of the rotating arm 512, and the rotating arm 512 can control the nozzle 514 Close to or away from the polishing pad 504.

In some embodiments, the polishing liquid 510 may be a polishing liquid that does not include polishing particles disclosed in the above embodiments of the present invention. It simply uses a chemical composition to react with the metal layer 206 on the semiconductor substrate 200 by chemical force. In some embodiments, the polishing liquid 510 may be a polishing liquid including polishing particles disclosed in the above embodiments of the present invention, which may further use the polishing particles to polish the metal layer 206 on the semiconductor substrate 200 with mechanical force.

In some embodiments, the polishing pad 504 is made of a sufficiently hard substance to allow the abrasive particles in the polishing liquid 510 to polish the metal layer 206 on the semiconductor substrate 200 through mechanical force. On the other hand, the polishing pad 504 must be soft enough to avoid scratching the metal layer 206 on the semiconductor substrate 200. In some embodiments, the polishing pad 504 is detachably attached to the rotating platform 502. For example, the polishing pad 504 can be connected to the rotating platform by an adhesive film or glue. 502 on. During the grinding process, the rotating platform 502 can be rotated by being driven by a first driving mechanism (for example, a motor (not shown)), so that the polishing pad 504 fixed thereon can rotate with the rotating platform 502.

Next, the polishing pad 504 is rotated, and the metal layer 206 formed on the semiconductor substrate 200 is brought into contact with the polishing surface of the polishing pad 504, and a part of the metal layer 206 is removed by chemical mechanical polishing.

As shown in FIG. 5, in some embodiments, the substrate holding device 506 and the polishing pad 504 rotate in the same direction (clockwise or counterclockwise). In some embodiments, the substrate holding device 506 and the polishing pad 504 can rotate in opposite directions. When the polishing pad 504 and the substrate holding device 506 rotate, the polishing liquid 510 can flow between the semiconductor device 20a / 20b and the polishing pad 504. The mechanical force and the chemical composition in the polishing liquid 510 react with the metal layer 206 on the semiconductor substrate 200, and the metal layer 206 on the semiconductor substrate 200 can be planarized. In some embodiments, the substrate holding device 506 is driven by a second driving mechanism (not shown).

Furthermore, as shown in FIG. 5, in some embodiments, the polishing device 500 may further include a pad conditioner 530 disposed above the polishing pad 504, and the polishing pad conditioner 530 is configured to remove Unwanted by-products generated during milling. In some embodiments, the polishing pad conditioner 530 is a diamond disk with a substrate and cut diamond particles embedded or encapsulated on the substrate. When the polishing pad 504 needs to be adjusted, the polishing pad adjuster 530 can contact the surface of the polishing pad 504, and the polishing pad 504 and the polishing pad adjuster 530 rotate so that the protrusions or edges on the diamond disk are relative to the polishing pad 504. The surface of the surface is moved, thereby polishing the polishing pad 504 and re-texturizing.

In addition, in some embodiments, the polishing pad adjuster 530 may also be provided with a brush made of nylon material to clean and remove residues remaining on the polishing pad 504 after the polishing process. After removing the remaining residue material, the polishing pad 504 can restore the original roughness to perform the polishing process on the same or another semiconductor substrate again.

In some embodiments, the chemical mechanical polishing apparatus 500 in FIG. 5 may further include a liquid distributor (not shown) configured to distribute a liquid A washing liquid, such as de-ionized water, is applied to the surface of the polishing pad 504, so that the polishing liquid 510 remaining on the surface of the polishing pad 504 after the polishing process can be cleaned. Furthermore, in some embodiments, the chemical mechanical polishing apparatus 500 may also include other stations, such as a cleaning station, a drying station, or other types of stations. Therefore, after the chemical mechanical polishing process, the semiconductor substrate 200 may perform a cleaning process at a cleaning station and a drying process at a drying station.

In the method for manufacturing a semiconductor device disclosed in the embodiments of the present invention, an organic base having a lone pair of electrons partially or completely replaces an inorganic base to attract metal ions generated during chemical mechanical polishing, and the reaction between the organic base and the metal ions Instead of the reaction between the inorganic base and the metal ions, the formation of metal particles is reduced or the effect of forming metal particles free is achieved.

In addition, in the method for manufacturing a semiconductor device, the metal chemical mechanical polishing process using the polishing liquid disclosed in the embodiment of the present invention is helpful to reduce or avoid metal re-generation on the surface of the integrated circuit during or after the metal chemical mechanical polishing process. Deposition phenomenon. Since there is no need to remove and re-deposit the metal formed on the surface of the integrated circuit after the metal chemical mechanical polishing process, unnecessary metal corrosion can be avoided and the effect of metal corrosion free can be achieved.

In some embodiments, a method for manufacturing a semiconductor device includes: forming a material layer on a semiconductor substrate; forming an opening in the material layer; depositing a metal layer in the opening and extending onto the material layer; and chemical mechanical polishing A part of the metal layer; one of the polishing liquids used in chemical mechanical polishing includes: an organic base having a lone pair of electrons; and an oxidant.

In some embodiments, a method for manufacturing a semiconductor device includes: forming a dielectric layer on a semiconductor substrate; forming an opening through the dielectric layer to expose the semiconductor substrate; depositing a barrier layer in the opening and the dielectric layer Depositing a metal layer in the opening and extending to the barrier layer; and chemically and mechanically polishing the metal layer until the barrier layer is exposed, wherein one of the polishing liquids used in chemical mechanical polishing includes: alkylamine, ammonia, or a combination of the foregoing; And an oxidant. Among them, an upper surface of the chemical mechanically polished metal layer is flush with an upper surface of one of the dielectric layers.

In some embodiments, a method for manufacturing a semiconductor device includes: depositing a metal layer on a semiconductor substrate; chemical mechanical polishing a portion of the metal layer; wherein a polishing liquid used in chemical mechanical polishing includes: an oxidant; and an organic base . Among them, the organic base includes a primary amine compound having the following formula (I), a secondary amine compound having the following formula (II), a tertiary amine compound having the following formula (III), and a quaternary ammonium having the following formula (IV) A compound, or a combination of the foregoing;

Wherein, R ¹ to R ¹⁰ may be the same or different, and each independently includes an unsubstituted or substituted C ₁ -C ₆ alkyl group and a C ₆ -C ₁₄ aromatic group. In some embodiments, the substituents on the alkyl group include a C ₁ -C ₈ alkoxy group, a C ₁ -C ₈ alkyl group, a nitro group, a halogen atom, a carboxyl group, or a hydroxyl group. In some embodiments, the substituents on the aromatic group include: C ₁ -C ₈ alkoxy, carboxyl, alkoxycarbonyl, C ₁ -C ₈ haloalkyl, C ₅ -C ₈ cycloalkyl, or C ₁ -C ₈ alkylthio group, wherein the weight% of the organic base is greater than 50% by weight, based on the total weight of the organic base and the optionally added inorganic base in the polishing liquid.

Although the present invention has been disclosed as above with several embodiments, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make any changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope of the appended patent application.

Claims (8)

A method for manufacturing a semiconductor device includes: forming a material layer on a semiconductor substrate; forming an opening in the material layer; depositing a metal layer in the opening and extending to the material layer; and chemical mechanical polishing a part The metal layer; wherein a polishing liquid used in the chemical mechanical polishing includes: an organic base having a lone pair of electrons; and an oxidant; wherein the organic base includes alkyl ammonium, ammonia, or the foregoing In combination, the alkylamine includes: a primary amine compound having the following formula (I), a secondary amine compound having the following formula (II), a tertiary amine compound having the following formula (III), and having the following formula (IV) A quaternary ammonium compound, or a combination thereof; Wherein, R ¹ to R ¹⁰ are the same or different, and each independently includes an unsubstituted or substituted C ₁ -C ₆ alkyl group and C ₆ -C ₁₄ aromatic group; wherein the substituents on the alkyl group include : C ₁ -C ₈ alkoxy, C ₁ -C ₈ alkyl, nitro, halogen atom, or carboxyl group, the substituents on the aromatic group include: C ₁ -C ₈ alkoxy, carboxyl, alkane oxycarbonyl group, C ₁ -C ₈ haloalkyl of, C ₅ -C ₈ cycloalkyl, or C ₁ -C ₈ alkylthio. The method for manufacturing a semiconductor device according to item 1 of the scope of patent application, wherein the organic base includes: methylamine, ethylamine, cyclohexylamine, dimethylamine, diethyl Diethylamine, methylethylamine, trimethylamine (TMA), triethylamine (TEA), N-methyl-N-ethylaniline, tetramethyl Tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), Or the foregoing composition. The method for manufacturing a semiconductor device according to item 1 of the scope of patent application, wherein the concentration of the organic base in the polishing liquid is greater than 10 ppm and less than or equal to 10,000 ppm. The method for manufacturing a semiconductor device according to item 1 of the scope of patent application, wherein the polishing liquid further includes an inorganic base, wherein the inorganic base includes: lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, and hydroxide Strontium, barium hydroxide, ammonium hydroxide, or a combination thereof. The method for manufacturing a semiconductor device according to item 1 of the application, wherein the polishing liquid further comprises an acid, wherein the acid includes: hydrochloric acid, sulfuric acid, nitric acid, boric acid, carbonic acid, hypophosphorous acid, phosphorous acid, phosphoric acid, and citric acid. , Formic acid, acetic acid, propionic acid, benzoic acid, salicylic acid, glyceric acid, oxalic acid, malonic acid, succinic acid, maleic acid, phthalic acid, malic acid, tartaric acid, lactic acid, or a combination thereof. A method for manufacturing a semiconductor device includes: forming a dielectric layer on a semiconductor substrate; forming an opening through the dielectric layer to expose the semiconductor substrate; depositing a barrier layer in the opening and neutralizing the dielectric layer Depositing a metal layer in the opening and extending to the barrier layer; and chemically and mechanically grinding the metal layer until the barrier layer is exposed; wherein an abrasive liquid used in the chemical mechanical grinding includes: alkyl ammonium (alkyl ammonium ), Ammonia (ammonia), or a combination of the foregoing; and an oxidant; wherein an upper surface of the metal layer chemically and mechanically ground is flush with an upper surface of one of the dielectric layers; wherein the alkylamine includes: A primary amine compound of the following formula (I), a secondary amine compound of the following formula (II), a tertiary amine compound of the following formula (III), a quaternary ammonium compound of the following formula (IV), or a combination thereof ; Wherein, R ¹ to R ¹⁰ are the same or different, and each independently includes an unsubstituted or substituted C ₁ -C ₆ alkyl group and C ₆ -C ₁₄ aromatic group; wherein the substituents on the alkyl group include : C ₁ -C ₈ alkoxy, C ₁ -C ₈ alkyl, nitro, halogen atom, or carboxyl group, the substituents on the aromatic group include: C ₁ -C ₈ alkoxy, carboxyl, alkane oxycarbonyl group, C ₁ -C ₈ haloalkyl of, C ₅ -C ₈ cycloalkyl, or C ₁ -C ₈ alkylthio. The method for manufacturing a semiconductor device according to item 6 of the patent application, wherein the step of chemically mechanically grinding the metal layer until the barrier layer is exposed includes The steps include: providing the polishing liquid to a polishing surface on a polishing pad; and rotating the polishing pad and bringing the metal layer into contact with the polishing surface to remove a portion of the metal layer until the barrier layer is exposed. A method for manufacturing a semiconductor device includes: depositing a metal layer on a semiconductor substrate; and a portion of the metal layer by chemical mechanical polishing; wherein a polishing liquid used in the chemical mechanical polishing includes: an oxidant; an organic base; and An inorganic base; wherein the organic base includes a primary amine compound having the following formula (I), a secondary amine compound having the following formula (II), a tertiary amine compound having the following formula (III), and having the following formula (IV) A quaternary ammonium compound, or a combination thereof; Wherein, R ¹ to R ¹⁰ are the same or different, and each independently includes an unsubstituted or substituted C ₁ -C ₆ alkyl group and C ₆ -C ₁₄ aromatic group; wherein the substituents on the alkyl group include : C ₁ -C ₈ alkoxy, C ₁ -C ₈ alkyl, nitro, halogen atom, or carboxyl group, the substituents on the aromatic group include: C ₁ -C ₈ alkoxy, carboxyl, alkane Oxycarbonyl, C ₁ -C ₈ haloalkyl, C ₅ -C ₈ cycloalkyl, or C ₁ -C ₈ alkylthio; wherein the weight% of the organic base is greater than 50% by weight, and the polishing liquid The total weight of the organic base and the inorganic base is used as a basis.