CN110153873B

CN110153873B - Polishing apparatus, inspection device, and method for polishing semiconductor substrate

Info

Publication number: CN110153873B
Application number: CN201810151144.5A
Authority: CN
Inventors: 蔡晴翔; 许加融; 陈科维; 黄惠琪
Original assignee: Taiwan Semiconductor Manufacturing Co TSMC Ltd
Current assignee: Taiwan Semiconductor Manufacturing Co TSMC Ltd
Priority date: 2018-02-14
Filing date: 2018-02-14
Publication date: 2021-06-11
Anticipated expiration: 2038-02-14
Also published as: CN110153873A

Abstract

The present disclosure provides a polishing apparatus, a detecting device and a polishing method of a semiconductor substrate, the polishing apparatus includes a rotating platform, a polishing pad, a polishing slurry supplier and at least one detecting device. The polishing pad is fixedly arranged on the rotary platform, and the polishing pad is configured to be rotated by the rotary platform. The slurry provider is configured to provide a slurry on the polishing pad. At least one detecting device is arranged in the polishing pad and is configured to detect the components and the corresponding concentration of the polishing slurry.

Description

Polishing apparatus, inspection device, and method for polishing semiconductor substrate

Technical Field

Embodiments of the present invention relate to semiconductor manufacturing technology, and more particularly, to a polishing system and a polishing method for monitoring slurry components during polishing.

Background

In recent years, semiconductor integrated circuits (semiconductor integrated circuits) have undergone exponential growth. With advances in integrated circuit materials and design techniques, multiple generations of integrated circuits are produced, with each generation having smaller, more complex circuits than the previous generation. As integrated circuits are developed, the functional density (i.e., the number of interconnections per chip area) typically increases as the geometries (i.e., the smallest elements or lines that can be produced in a process) shrink. Generally, such a downscaling process provides the benefits of increased production efficiency and reduced manufacturing costs, however, such a downscaling process also increases the complexity of manufacturing and producing integrated circuits.

In semiconductor device fabrication, Chemical Mechanical Polishing (CMP), a popular implementation of integrated circuit formation, plays a significant role. In general, chemical mechanical polishing is applied to a planarization process of a semiconductor wafer. Chemical mechanical polishing is the polishing of a wafer by both physical and chemical forces. When the wafer is on a polishing pad, a clamping device applies a downward pressure on the back surface of the wafer. Then, when a polishing slurry containing corrosive and reactive chemicals passes under the wafer, the polishing pad and the wafer can rotate relatively to polish the wafer. Chemical mechanical polishing is an effective way to achieve planarization of the entire wafer.

Although conventional semiconductor processing tools, including wafer polishing systems, have been satisfactory for the above general purpose, such semiconductor processing tools and filtering methods have not been satisfactory in every aspect.

Disclosure of Invention

Some embodiments of the present invention provide a polishing apparatus, which includes a rotating platen, a polishing pad, a slurry supplier, and at least one detecting device. The polishing pad is fixedly arranged on the rotary platform, and the polishing pad is configured to be rotated by the rotary platform. The slurry provider is configured to provide a slurry on the polishing pad. At least one detecting device is arranged in the polishing pad and is configured to detect the components and the corresponding concentration of the polishing slurry.

The embodiment of the invention also provides a detection device which is arranged in the grinding pad and comprises a plurality of detection modules and a processing chip. Each detection module comprises a reaction area and a detection electrode. The reaction zone is configured to receive a polishing slurry on the polishing pad, and the reaction zone includes a reaction material corresponding to a component of the polishing slurry. The detection electrode is configured to output a detection signal when the components of the slurry react with the reactive material. The processing chip is configured to receive the detection signal to obtain a detection information including the composition and concentration of the slurry.

An embodiment of the invention provides a method for polishing a semiconductor substrate, which includes providing a polishing slurry to a polishing surface of a polishing pad. Furthermore, the method for polishing the semiconductor substrate further comprises the step of arranging the semiconductor substrate on the polishing surface to carry out polishing treatment. The method for polishing a semiconductor substrate further comprises detecting the components and concentration of the polishing slurry by at least one detection device disposed on the polishing pad.

Drawings

FIG. 1 is a schematic view of a polishing apparatus according to some embodiments of the present invention.

Fig. 2 and 3 are schematic diagrams illustrating the substrate holding apparatus holding a semiconductor substrate by a substrate holder according to some embodiments of the invention.

FIGS. 4 and 5 are schematic diagrams illustrating the operation of a substrate clamping device clamping a semiconductor substrate onto a polishing pad according to some embodiments of the present invention.

Fig. 6 is a top view of a polishing pad according to some embodiments of the invention.

FIG. 7 is a schematic view of a detection device according to some embodiments of the invention.

FIG. 8 is a partial cross-sectional view of a detection device disposed on a polishing pad according to some embodiments of the invention.

FIG. 9 is a graph illustrating the concentration of components in a slurry according to some embodiments of the invention.

FIG. 10 is a top view of a polishing pad according to another embodiment of the invention.

Fig. 11 is a flow chart of a method of polishing a semiconductor substrate according to some embodiments of the present invention.

Description of reference numerals:

100 grinding apparatus

102 substrate bearing seat

200 processing chamber

202 rotating platform

204 grinding pad

2041 grinding surface

2043 groove

206 substrate clamping device

207 substrate carrier

208 slurry supplier

2081 rotating arm

2083 nozzle

210 abrasive slurry

212 polishing pad conditioner

214 clamping member

216 baffle ring

300 semiconductor substrate

400 detection device

401 upper surface

402 detection module

4021 reaction zone

4022 reaction mass

4023 detection electrode

4025 detection electrode

4027A lead

404 processing chip

406 communication circuit

408 heating module

500 monitoring device

600 notification module

700 grinding method

Components A to D

Initial concentration of a 1-d 1

Cx1 central rotating shaft

d2 Medium concentration in grinding

Central zone of NPC

NPE edge zone

PSA grinding zone

time t1

T1 first thickness

T2 second thickness

Width of Wp

S100, S102, S103, S104, S106, S108, S110, S112, S114, S116 operations

Detailed Description

While the following description of the present invention has been described with reference to specific embodiments, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing may readily produce alterations to, variations of, and equivalents to such embodiments. Of course, the present disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

Spatially relative terms, such as "below," "lower," "above," "upper," and the like, may be used hereinafter with respect to elements or features in the figures to facilitate describing a relationship between one element or feature and another element(s) or feature(s) in the figures. These spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, the device may be oriented in different directions (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. In addition, if the embodiments describe a first feature formed over or on a second feature, that is, the description may include the first feature being in direct contact with the second feature, or additional features may be formed between the first and second features, such that the first and second features are not in direct contact.

The same reference numbers and/or letters may be repeated in the various embodiments below for simplicity and clarity, and are not intended to limit the particular relationships between the various embodiments and/or structures discussed. In addition, in the drawings, the shape or thickness of the structure may be exaggerated for simplification or convenience of marking. It is to be understood that elements not specifically shown or described may exist in various forms well known to those skilled in the art.

In the fabrication of semiconductor devices, chemical mechanical polishing is a process used to fabricate semiconductor devices. Specifically, chemical mechanical polishing is a process of homogenizing and planarizing the surface of a semiconductor substrate (e.g., a wafer) using a combination of chemical and mechanical forces. A wafer having Integrated Circuit (IC) dies is placed in a processing chamber of a cmp system and may be planarized or polished at various stations. The chemical mechanical polishing process may planarize the surface of the dielectric layer, the semiconductor layer, and/or the conductive material layer of the wafer, for example.

Chemical mechanical polishing systems typically have a rotatable polishing platen with a polishing pad attached to the platen. In some chemical mechanical polishing processes, a semiconductor substrate is placed upside down in a clamping device, and the semiconductor substrate is pressed by the clamping device toward a polishing pad. In addition, during the polishing process, a fluid supply in the cmp system may provide a slurry with chemicals and micro-polishing particles onto the polishing pad while the semiconductor substrate is held toward the rotating polishing pad. In some embodiments, the polishing pad can also rotate relative to the polishing pad. In some embodiments, the semiconductor substrate is rotated in the same direction as the polishing pad. In other embodiments, the semiconductor substrate and the polishing pad rotate in different directions.

FIG. 1 is a schematic diagram of a polishing apparatus 100 according to some embodiments of the invention. As shown in fig. 1, the polishing apparatus 100 includes a processing chamber 200 to form an enclosed space for accommodating components in the polishing apparatus 100 to be described later. One or more load ports (not shown) are coupled to the processing chamber 200 to allow a semiconductor substrate 300 or a plurality of semiconductor substrates to enter or exit the polishing apparatus 100. For example, the semiconductor substrate entering or exiting may be a wafer, such as a production wafer (production wafer) or a test wafer. In some embodiments, the radius of the semiconductor substrate is between about 200mm and 600 mm. Additionally, in some embodiments, the radius of the semiconductor substrate may be between about 300mm and 450 mm. The radius of the semiconductor substrate is not limited to this embodiment.

According to some embodiments, the semiconductor substrate (wafer) 300 may be made of silicon, germanium, or other semiconductor materials. According to some embodiments, the semiconductor substrate 300 may be made of a composite semiconductor, such as silicon carbide (SiC), gallium arsenide (GaAs), indium arsenide (InAs), or indium phosphide (InP). According to some embodiments, the semiconductor substrate 300 may be made of an alloy semiconductor, such as silicon germanium (SiGe), silicon germanium carbon (SiGeC), gallium arsenide phosphide (GaAsP), or indium gallium phosphide (GaInP). According to some embodiments, the semiconductor substrate 300 may be a silicon-on-insulator (SOI) or germanium-on-insulator (GOI) substrate.

Furthermore, as shown in fig. 1, the polishing apparatus 100 may include a rotating platen 202, a polishing pad 204, a substrate holder 206, and a slurry provider 208 disposed in the processing chamber 200. The polishing pad 204 is fixedly disposed on the rotating platform 202 and connected to the rotating platform 202, and the polishing pad 204 is configured to be driven by the rotating platform 202 to rotate synchronously around the central rotation axis Cx 1. The substrate holding device 206 is disposed above the polishing pad 204 and configured to hold a semiconductor substrate 300 moving along a direction parallel to the central rotation axis Cx 1. The slurry provider 208 has a liquid outlet above the polishing pad 204 configured to apply a slurry 210 to the polishing pad 204.

During the polishing process, the slurry provider 208 may apply the slurry 210 to the polishing pad 204. In some embodiments, the slurry supplier 208 is connected to a tank or a reservoir (not shown) containing the slurry 210. In some embodiments, the slurry supplier 208 may include a rotating arm 2081 and a nozzle 2083 (e.g., as the aforementioned liquid outlet), the nozzle 2083 is disposed at one end of the rotating arm 2081, and the rotating arm 2081 can control the nozzle 2083 to be close to or away from the polishing pad 204. The slurry 210 contains reactive chemicals (reactive chemicals) that react with the surface of the semiconductor substrate 300. The slurry 210 may also contain polishing particles to mechanically polish the semiconductor substrate 300.

In some embodiments, the polishing pad 204 is made of a material hard enough to allow the polishing particles in the slurry 210 to mechanically polish the semiconductor substrate 300. On the other hand, the polishing pad 204 is also soft enough to avoid scratching the semiconductor substrate 300. In some embodiments, the polishing pad 204 is removably and adhesively attached to the platen 202, for example, the polishing pad 204 may be attached to the platen 202 by an adhesive film (adhesive film) or glue, etc. During polishing, the platen 202 may be rotated by a first driving mechanism (e.g., a motor, not shown) such that the polishing pad 204 fixed thereon rotates with the platen 202.

The substrate holding device 206 may also rotate the semiconductor substrate 300 thereon during the polishing process. In some embodiments, as shown in FIG. 1, the substrate holder 206 and the polishing pad 204 rotate in the same direction (clockwise or counterclockwise). In other embodiments, the substrate holder 206 and the polishing pad 204 may rotate in opposite directions. The polishing slurry 210 may flow between the semiconductor substrate 300 and the polishing pad 204 as the polishing pad 204 and the substrate holder 206 rotate. The surface of the semiconductor substrate 300 may be planarized by a mechanical force and a chemical reaction between the chemical substances in the slurry 210 and the surface of the semiconductor substrate 300. In some embodiments, the substrate holding device 206 is driven by a second driving mechanism (not shown).

Furthermore, as shown in fig. 1, the polishing apparatus 100 may further comprise a polishing pad conditioner 212 disposed within the processing chamber 200 above the polishing pad 204, the polishing pad conditioner 212 configured to remove unwanted byproducts generated during the polishing process. In some embodiments, the polishing pad conditioner 212 is a diamond disk (diamond disk) having a substrate and embedded or encapsulated cutting diamond particles on the substrate. When the polishing pad 204 needs to be adjusted, the polishing pad conditioner 212 may contact the surface of the polishing pad 204, and the polishing pad 204 and the polishing pad conditioner 212 rotate such that the protrusions or edges on the diamond disk move relative to the surface of the polishing pad 204, thereby polishing and tissue-refreshing (re-texturing) the polishing pad 204.

In some embodiments, a brush made of Nylon material may be disposed on the polishing pad conditioner 212 to clean and remove residue material remaining on the polishing pad 204 after the polishing process. After removing the residual residue, the polishing pad 204 can restore the original roughness for polishing the same or another semiconductor substrate again.

Furthermore, as shown in fig. 1, the polishing apparatus 100 may further include a detection device 400, a monitoring device 500, and a notification module 600. The inspection apparatus 400 is configured to inspect the thickness of the semiconductor substrate 300 to generate a thickness information. In some embodiments, the detection device 400 is disposed in the polishing pad 204 and configured to continuously detect the composition and corresponding concentration of the polishing slurry 210 during the polishing process of the semiconductor substrate 300. For example, the detection device 400 can detect the concentration of cobalt, copper, chromium, magnesium, nickel, zinc, aluminum, etc. in the slurry 210. The substance detectable by the detection apparatus 400 is not limited to this embodiment. In some embodiments, the detecting device 400 detects the components and the corresponding concentration of the polishing slurry 210 before the semiconductor substrate 300 is polished. Furthermore, the detecting device 400 can also detect the concentration of the substance generated by the chemical reaction of the slurry 210 during the polishing process. The detection device 400 may detect the concentration of a substance generated when the semiconductor substrate 300 is polished (for example, metal particles).

The monitoring device 500 is configured to monitor the concentration of each substance in the slurry 210. When the concentration of a substance or substances changes beyond expectations, the monitoring device 500 can send a control signal to the notification module 600, so that the notification module 600 sends a notification message. For example, the notification module 600 may issue a warning message, such as a warning tone or a flashing light, to notify the user. In some embodiments, the monitoring device 500 may be a computer device of the polishing apparatus 100, and the notification module 600 may be a display screen, and the notification module 600 may display a dialog window to notify the user according to the control signal.

In some embodiments, the monitoring device 500 may be a computer device in the polishing apparatus 100, and may include a processor and a storage circuit (not shown). The processor may be a microprocessor or a central processing unit. The storage circuit may be a memory storing a plurality of programs or instructions. The monitoring device 500 may generate a driving signal to a plurality of driving mechanisms (such as the first driving mechanism or the second driving mechanism) in the polishing apparatus 100 to control the operations of the components in the polishing system 100. For example, the monitoring device 500 may control the rotation of the rotating platen 202, the operation of the slurry provider 208, the substrate holding device 206, and the polishing pad conditioner 212.

It should be noted that the polishing apparatus 100 shown in fig. 1 is only an example of the embodiment of the present invention, and is not intended to limit the scope thereof. In various embodiments, the components of the polishing apparatus 100 in fig. 1 can be added or deleted according to actual requirements. For example, the polishing apparatus 100 may further comprise a liquid distributor (not shown) configured to distribute a cleaning liquid, such as de-ionized water (de-ionized water), to the surface of the polishing pad 204, so that the particles and slurry 210 remaining on the surface of the polishing pad 204 after the polishing process can be cleaned. Moreover, the polishing apparatus 100 may also include other stations (stations), such as a cleaning station, a drying station, or other types of stations. Accordingly, after a chemical polishing process (CMP process), the semiconductor substrate may be subjected to a cleaning process at a cleaning station and a drying process at a drying station.

Referring to fig. 2 and 3, fig. 2 and 3 are schematic operation diagrams of the substrate holding device 206 holding the semiconductor substrate 300 by a substrate holder 102 according to some embodiments of the invention. As shown in fig. 2, the substrate holding apparatus 206 includes a substrate carrier 207 configured to hold and secure a semiconductor substrate 300 during a polishing process. In this embodiment, the substrate carrier 207 has a plurality of gas passages 2071 in communication with a gas control module 209. Additionally, a clamp 214 may be disposed below the substrate carrier 207, and the clamp 214 may be a thin film structure and made of a flexible and extensible material. For example, in some embodiments, the clamp 214 may be made of ethylene propylene rubber, neoprene rubber, nitrile rubber, or the like. As shown in FIG. 2, the clamping member 214 includes a plurality of segments, and each segment has a passage (not shown) therein, which is respectively connected to the gas passage 2071 and the gas control module 209.

As shown in fig. 2, the substrate holding device 206 is moved over the substrate carrier 102 to bring the holding members 214 close to the semiconductor substrate 300. Next, the gas control module 209 causes the gas passages 2071 and the plurality of passages in the clamping member 214 to be in a vacuum state. Therefore, as shown in fig. 3, the semiconductor substrate 300 is attracted to the bottom of the clamping member 214 and moves away from the substrate holder 102 along with the substrate clamping device 206. It is noted that, in this embodiment, the substrate carrier 102 is a carrier (not shown in figure 1) disposed within the processing chamber 200. However, in other embodiments, the substrate carrier 102 may be a carrier for other chambers of the polishing apparatus 100.

As shown in fig. 3, the substrate holding device 206 may further include a retaining ring 216 disposed at the bottom of the substrate carrier 207 and surrounding the clamp 214. When the substrate holder 206 holds the semiconductor substrate 300, the central axis of the substrate holder 206 is aligned with the center of the semiconductor substrate 300, such that the edge of the semiconductor substrate 300 and an inner ring surface 2161 of the baffle ring 216 have the same gap Gp therebetween.

Referring to fig. 4 and 5, fig. 4 and 5 are schematic views illustrating the substrate holding device 206 holding the semiconductor substrate 300 onto the polishing pad 204 according to some embodiments of the present invention. As shown in fig. 4, the polishing pad 204 is positioned on the rotating platen 202 and the substrate holder 206 is moved over the polishing pad 204. Fig. 4 of the embodiment of the invention only shows a part of the structure of the polishing pad 204 and the rotating platen 202, i.e., the structure of the polishing pad 204 in fig. 4 is not the central part of the polishing pad 204. In contrast, as shown in FIG. 1, the central rotation axis Cx1 of the polishing pad 204 can be used as the rotation axis of the polishing pad 204, and the polishing pad 204 shown in FIG. 4 is configured to be offset from the central rotation axis Cx1 of the polishing pad 204. For example, the structure of the polishing pad 204 shown in fig. 4 can be a left portion or a right portion of the polishing pad 204 in fig. 1.

As shown in fig. 5, the substrate holder 206 moves toward the polishing pad 204 and abuts against the polishing pad 204. Next, the gas control module 209 stops the vacuum state in the gas passages 2071 so that the semiconductor substrate 300 is not sucked by the clamping members 214. Thereafter, the gas control module 209 may provide gas into the clamp 214 through the gas channel 2071, such that the clamp 214 inflates and expands, thereby abutting and providing a pushing force to press down the semiconductor substrate 300.

It is noted that the retainer ring 216 has one or more grooves (not shown) towards the bottom of the polishing pad 204, such that when the substrate holder 206 rotates against the polishing pad 204 and the retainer ring 216 directly contacts the polishing pad 204, the slurry 210 can flow in or out through the grooves on the bottom surface of the retainer ring 216. In certain embodiments, the slinger 216 may be made of a wear-resistant material, such as plastic, ceramic, or polymer. For example, the baffle ring 216 may be made of polyphenylene sulfide (PPS), poly diether ketone (PEEK), or a mixture thereof. The stopper ring 216 may be made of a polymer such as polyurethane (polyurethane), copolyester (polyester), polyether ester (polyether), or polycarbonate (polycarbonate), and the material of the stopper ring 216 is not limited to this embodiment.

The retainer ring 216 may be used to maintain the position of the semiconductor substrate 300 during a Chemical Mechanical Polishing (CMP) process to prevent the semiconductor substrate 300 from shifting from the central axis of the substrate holder 206 during rotation and thus rotating off of the polishing pad 204. As shown in fig. 5, the substrate holder 206 drives the semiconductor substrate 300 to rotate and abut against the rotating polishing pad 204, so as to realize the chemical mechanical polishing process of the semiconductor substrate 300 and achieve the purpose of planarization of the semiconductor substrate 300.

During the polishing process of the semiconductor substrate 300, some components or substances in the slurry 210 may remain on the semiconductor substrate 300, thereby affecting the planarization result of the semiconductor substrate 300 after the polishing process. Therefore, by monitoring the concentration change of each component in the slurry 210, it is possible to know whether or not a specific component remains on the semiconductor substrate 300. Generally, if the components in the slurry 210 do not remain on the semiconductor substrate 300, the concentration of each component in the slurry 210 changes steadily over time, for example, decays steadily over time. On the other hand, if the concentration of a specific component (e.g., aluminum or cobalt) in the slurry 210 is too strongly attenuated, it may indicate that aluminum or cobalt is attached to the semiconductor substrate 300, and the planarization of the semiconductor substrate 300 is affected.

Referring to fig. 6, fig. 6 is a top view of a polishing pad 204 according to some embodiments of the invention. As shown in fig. 6, the polishing pad 204 is used for polishing a polishing surface 2041 of the semiconductor substrate 300, which has a polishing region PSA and a non-polishing region defined thereon, and the semiconductor substrate 300 is configured to be polished in the polishing region PSA, as shown in fig. 6. The width Wp of the polishing region PSA is larger than the diameter of the semiconductor substrate 300, and the semiconductor substrate 300 can be controlled to be polished in one of the polishing regions PSA.

In some embodiments, as shown in fig. 6, the non-polishing region may include a central region NPC and an edge region NPE, the polishing region PSA is between the central region NPC and the edge region NPE, and the detecting device 400 may be disposed on the non-polishing region to prevent the semiconductor substrate 300 from being scratched by the contact between the detecting device 400 and the semiconductor substrate 300 during the polishing process. In this embodiment, the detecting device 400 is disposed on the edge zone NPE. When the semiconductor substrate 300 is being polished and the slurry 210 flows through the detecting device 400, the detecting device 400 can detect the components and the corresponding concentration of the slurry 210 in real time. In some embodiments, the detecting device 400 can continuously detect the components and corresponding concentrations of the slurry 210, but is not limited thereto. For example, the detection device 400 can perform detection at regular intervals.

Referring to fig. 7, fig. 7 is a schematic diagram of a detection apparatus 400 according to some embodiments of the invention. In some embodiments, the detection device 400 may include a plurality of detection modules 402, a processing chip 404, and a communication circuit 406. In this embodiment, as shown in fig. 7, the detecting device 400 includes 12 detecting modules 402 electrically connected to the processing chip 404 respectively. Each detection module 402 is configured to detect a specific component of the slurry 210. That is, the detecting device 400 in fig. 7 can be configured to detect 12 components and corresponding concentrations in the slurry 210. The number of detection modules 402 on the detection apparatus 400 is not limited to this embodiment, and may be increased or decreased according to actual needs.

In some implementations, the detecting module 402 includes a reaction region 4021 (or called reaction chamber), a detecting electrode 4023 and another detecting electrode 4025. The reaction region 4021 may have a reactive material 4022 disposed on the detecting

electrodes

4023 and 4025, and the reactive material 4022 may be configured to detect a specific component of the slurry 210, such as aluminum, cobalt, etc. In this embodiment, the reactant material 4022 is a solid, but is not limited thereto, and may be a liquid in other embodiments. When a portion of the slurry 210 flows into the reaction region 4021, the specific component (e.g., aluminum) reacts with the reactant 4022 to generate a voltage change, so that the detection electrode 4023 (e.g., positive electrode) and the detection electrode 4025 (e.g., negative electrode) can transmit the voltage change as a detection signal to the processing chip 404 through the wire 4027. Thus, the processing chip 404 can perform a table lookup after receiving the detection signal to obtain a detection information including the composition and the corresponding concentration of the slurry 210. In this embodiment, the processing chip 404 may refer to a voltage concentration lookup table for performing a lookup, and the voltage concentration lookup table may include information of a plurality of voltages and corresponding concentrations thereof. In some embodiments, the voltage concentration comparison table may include information regarding the voltage and corresponding concentration of the components in the slurry 210.

Then, the processing chip 404 can transmit the detection information to the monitoring device 500 through the communication circuit 406, so that the monitoring device 500 can monitor the components and the corresponding concentrations in the slurry 210 through the detection device 400. In some embodiments, the monitoring device 500 is in wired communication with the communication circuit 406 of the detection device 400. In other embodiments, the monitoring device 500 communicates with the communication circuit 406 of the detection device 400 via wireless transmission. In addition, in some embodiments, the detection device 400 can also wirelessly transmit the detection information to a portable electronic device outside the polishing apparatus 100, such as a smart phone of a monitoring person.

In some embodiments, the processing chip 404 may be a Micro-controller Unit (MCU), such as an integrated chip having a central processing Unit, a memory, a timer/counter, an input/output interface, etc. integrated therein, and having advantages of simple input/output interface and small size.

Referring to fig. 8, fig. 8 is a partial cross-sectional view of a detection device 400 disposed on a polishing pad 204 according to some embodiments of the invention. As shown in FIG. 8, the polishing pad 204 may have a recess 2043, and the detecting device 400 may be accommodated in the recess 2043. It is noted that an upper surface 401 of the detecting device 400 is substantially aligned with the polishing surface 2041 of the polishing pad 204. By such a design, the slurry 210 can flow through the detecting device 400 without remaining at the boundary between the groove 2043 and the detecting device 400. Furthermore, as shown in fig. 8, the reaction zone 4021 may be a bowl-shaped groove, so that the slurry 210 may flow into the reaction zone 4021 by centrifugal force when the polishing pad 204 rotates. Then, the reactive material 4022 in the reaction zone 4021 reacts with a specific component in the slurry 210, and finally the slurry 210 in the reaction zone 4021 is driven out of the reaction zone 4021 by the centrifugal force.

In this embodiment, it is noted that the shape of the reaction zone 4021 is not limited to the bowl shape shown in fig. 8, but may be designed to be rectangular or other shapes that facilitate the inflow or outflow of the slurry 210 in other embodiments. Furthermore, for clarity, the extending directions of the detecting

electrodes

4023 and 4025 in fig. 8 are shown as being perpendicular to the upper surface 401 of the detecting device 400, but the extending directions of the detecting

electrodes

4023 and 4025 may also be parallel to the upper surface 401 as shown in fig. 7. In addition, in this embodiment, the detecting electrode 4023 and the detecting electrode 4025 are comb-shaped electrodes (comb-type electrodes), and the detecting electrode 4023 or the detecting electrode 4025 may have a plurality of platelets at one end thereof in the reaction region 4021 to increase the contact area with the polishing slurry 210, thereby increasing the detection speed.

In addition, in some embodiments, the detection apparatus 400 may further comprise a heating module 408 connected to the reactant material 4022 in the reaction zone 4021. For example, when the reactive material 4022 continuously reacts with a specific material in the slurry 210 over a period of time, the detection efficiency or sensitivity of the reactive material 4022 may be reduced. Thus, the processing chip 404 can control the heating module 408 to heat the reactive species 4022 in the reaction zone 4021 to restore the detection efficiency or sensitivity of the reactive species 4022. Note that the method of recovering the detection efficiency or sensitivity of the reactive substance 4022 is not limited to the heating method of this embodiment.

Referring to fig. 1 and 9, fig. 9 is a graph illustrating the concentration variation of some components in the polishing slurry 210 according to some embodiments of the present invention. For convenience of illustration, fig. 9 shows only four curves of the slurry 210, but fig. 9 may also include curves of more components. As shown in fig. 9, when the time is 0, that is, when the polishing slurry 210 is not in contact with the semiconductor substrate 300 and the polishing process is performed or the polishing process is just started, the components a to D in the polishing slurry 210 have initial concentrations a1 to D1, respectively. In this embodiment, the initial concentrations a1 d1 are within a predetermined concentration range. For example, if the initial concentration of each component of the slurry 210 is within a predetermined range, it indicates that the quality of the slurry 210 meets the requirement of the application, and the slurry can be used for polishing without affecting the planarization effect of the semiconductor substrate 300. Next, when the semiconductor substrate 300 starts the polishing process, the concentrations of the components a to D gradually decrease.

It is noted that, as shown in fig. 9, the concentration of the component D at the time t1 decays to a polishing medium concentration D2, and the monitoring device 500 can obtain a decay ratio according to the initial concentration D1 and the polishing medium concentration D2. In this embodiment, the attenuation ratio may be defined as (d1-d2) × 100%/d 1, and a predetermined attenuation ratio, for example, 3%, may be stored in the monitoring device 500. In a typical polishing process, the concentration of each component in the slurry 210 may be attenuated more gradually, for example, the attenuation ratio may be smaller than a predetermined attenuation ratio (e.g., 3%), which means that no component remains on the semiconductor substrate 300 in the slurry 210. However, when the attenuation ratio of the component D in fig. 9 is larger than a predetermined attenuation ratio (e.g., 3%), the monitoring apparatus 500 may thus determine that the component D may remain on the semiconductor substrate 300. In this embodiment, the predetermined attenuation ratio of the slurry 210 is defined as 3%, but not limited thereto, and may be defined according to each component of the slurry 210.

When the monitoring device 500 determines that the attenuation ratio is greater than the predetermined attenuation ratio, the monitoring device 500 may control the notification module 600 to issue a warning message to notify the user that the semiconductor substrate 300 being processed may have a problem of material (e.g., metal particles such as aluminum, cobalt, etc.) remaining therein. In addition, in some embodiments, the monitoring device 500 may mark the semiconductor substrate 300 being processed, and then control the marked semiconductor substrate 300 to perform a cleaning operation again after the polishing process, so as to remove the residual material (such as metal particles of aluminum, cobalt, and the like) on the marked semiconductor substrate 300, thereby preventing the residual metal particles from affecting the subsequent processes and reducing the yield of the semiconductor substrate 300.

In addition, in some embodiments, when the monitoring device 500 determines that the concentration of some component is increased too much (e.g., more than 3% of the original concentration), the monitoring device 500 may also control the notification module 600 to issue a warning message.

Based on the design of the detecting device 400, the polishing apparatus 100 of the embodiment of the invention can detect and monitor the concentration of each component in the slurry 210 once, many times or continuously during the polishing process of the semiconductor substrate 300, so as to ensure that some components in the slurry do not remain on the semiconductor substrate 300. When there is a substance remaining on the semiconductor substrate 300, the monitoring device 500 can immediately know the substance, and does not need to wait for the semiconductor substrate 300 to complete a polishing process before performing a detection.

Referring to fig. 10, fig. 10 is a top view of a polishing pad 204 according to another embodiment of the invention. In this embodiment, the polishing apparatus 100 may comprise two detecting devices 400, wherein one detecting device 400 is disposed at the center (within the central region NPC) of the polishing pad 204, and the other detecting device 400 is disposed on the edge region NPE. The polishing slurry 210 is detected in a similar manner as the previous embodiment, but in this embodiment, the monitoring device 500 controls the slurry supplier 208 to supply the slurry 210 to the detecting device 400 located at the center of the polishing pad 204 for detection before the polishing process.

If the components in the slurry 210 are different from the initial concentrations shown in FIG. 9, for example, the initial concentration of component A is less than a1, and the initial concentration of component B is less than B1 and exceeds the predetermined range of the initial concentrations, it indicates that the quality of the currently used slurry 210 does not meet the use requirement, and thus the planarization effect of the semiconductor substrate 300 after the polishing process may be affected. Accordingly, the monitoring device 500 may control the notification module 600 to send a warning message or a notification message, or may also stop the operation of the polishing apparatus 100 to facilitate the replacement of a new slurry 210 meeting the usage requirement. Based on the design of the inspection apparatus 400 of this embodiment, it can be known that the slurry 210 does not meet the requirement before the polishing process and is replaced in time to ensure that the planarization effect of the semiconductor substrate 300 is not affected in the subsequent polishing process.

Referring to fig. 11, fig. 11 is a flow chart of a method 700 for polishing a semiconductor substrate 300 according to some embodiments of the invention. In operation S100, the monitoring apparatus 500 controls the slurry supplier 208 to supply the slurry 210 to the detecting apparatus 400 located at the center of the polishing pad 204. In operation S102, the composition of the non-polishing slurry 210 and the corresponding detection information such as the initial concentration are detected by the detection device 400 disposed at the center of the polishing pad 204. Next, in operation S103, the monitoring device 500 may determine whether the initial concentration of the slurry 210 is within a predetermined range according to the detection information. If the current position is within the predetermined range, continue to execute operation S104; if the predetermined range is exceeded, operation S116 is performed.

Next, in operation S104, the platen 202 rotates the polishing pad 204. In operation S106, the monitoring device 500 controls the slurry supplier 208 to move to the edge of the polishing pad 204 and supply the slurry 210 to the polishing surface 2041 of the polishing pad 204 once, multiple times or continuously. In operation S108, the substrate holding device 206 disposes the semiconductor substrate 300 on the polishing surface 2041 to perform a polishing process.

In operation S110, the composition and the concentration during polishing of the polishing slurry 210 during the polishing process are detected by another detecting device 400 disposed at the edge of the polishing pad 204 once, multiple times, or continuously. In operation S112, the monitoring apparatus 500 compares the initial concentration of the slurry 210 with the polishing concentration to obtain a decay ratio. In operation S114, the monitoring apparatus 500 determines whether the attenuation ratio is greater than a predetermined attenuation ratio. If the attenuation ratio is greater than the predetermined attenuation ratio, operation S116 is performed. If the attenuation ratio is less than the predetermined attenuation ratio, operation S114 is continuously performed. In operation S116, the monitoring apparatus 500 controls the notification module 600 to issue a notification message, such as a warning message or a dialog window or a flashing light. It is to be noted that the foregoing operation is not limited to this embodiment, and the order of the operations may be changed or modified, or additional operations may be added. For example, operations S100-S103 may also be omitted from the polishing method 700.

An embodiment of the invention provides a polishing apparatus 100 having a detection device 400 embedded or embedded in a polishing pad 204. When the semiconductor substrate 300 is subjected to a polishing process, the detecting device 400 can detect the concentration of each component in the slurry 210 once, many times or continuously, and does not need to perform complicated procedures such as manually sampling the slurry 210, transporting the slurry to a laboratory, and then detecting the slurry. By the design of the inspection apparatus 400 and the monitoring apparatus 500 according to the embodiment of the present invention, the contamination problem during the transportation of the slurry 210 to the laboratory can be avoided, the steps of the inspection process can be reduced, and the concentration of the components in the slurry 210 can be obtained in real time, so as to ensure that the components in the slurry 210 do not remain on the semiconductor substrate 300.

The polishing apparatus 100 may further include another detecting device 400 disposed at the center of the polishing pad 204, and the monitoring device 500 may detect and determine whether the concentration of the component of the polishing slurry 210 is within a predetermined range by the detecting device 400 before or immediately after the polishing process is performed on the semiconductor substrate 300. Therefore, based on the design of some embodiments of the present invention, it can be known that the slurry 210 does not meet the usage requirement before the polishing process and is replaced in time, so as to avoid affecting the planarization effect of the semiconductor substrate 300 in the subsequent polishing process.

An embodiment of the invention provides a polishing apparatus, which includes a rotating platen, a polishing pad, a slurry supplier and at least one detecting device. The polishing pad is fixedly arranged on the rotary platform, and the polishing pad is configured to be rotated by the rotary platform. The slurry provider is configured to provide a slurry on the polishing pad. At least one detecting device is arranged in the polishing pad and is configured to detect the components and the corresponding concentration of the polishing slurry.

According to some embodiments, the polishing pad includes a recess, the detecting device is disposed in the recess, and an upper surface of the detecting device is aligned with a polishing surface of the polishing pad facing a semiconductor substrate.

According to some embodiments, a polishing surface of the polishing pad includes a polishing region configured to polish a semiconductor substrate and a non-polishing region, and the detecting device is disposed in the non-polishing region.

According to some embodiments, the polishing apparatus comprises two detecting devices, the non-polishing region comprises a central region and an edge region of the polishing surface, the polishing region is between the central region and the edge region, one of the detecting devices is disposed in the central region of the polishing pad, and the other detecting device is disposed in the edge region of the polishing pad.

According to some embodiments, the detection device further comprises a communication circuit configured to transmit the detection information to a monitoring device by wired or wireless transmission.

According to some embodiments, the step of detecting the composition and concentration of the polishing slurry further comprises detecting the composition and initial concentration of the polishing slurry without polishing treatment by a detecting device disposed at the center of the polishing pad; and detecting the composition of the polishing slurry in the polishing process and the concentration during polishing by another detection means provided at the edge of the polishing pad.

According to some embodiments, the method further comprises providing a polishing slurry to a detection device located at the center of the polishing pad before the polishing process. Moreover, the method for polishing the semiconductor substrate further comprises the step of judging whether the initial concentration of the polishing slurry is within a predetermined concentration range.

According to some embodiments, the method for polishing a semiconductor substrate further comprises comparing the initial concentration of the slurry with the polishing concentration to obtain an attenuation ratio; and when the attenuation proportion is larger than a preset attenuation proportion, a warning message is sent out.

Although the embodiments and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present disclosure. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps. Furthermore, each claim constitutes a separate embodiment, and combinations of different claims and embodiments are within the scope of the disclosure.

Claims

1. A polishing apparatus, comprising:

a rotating platform;

a polishing pad fixedly disposed on the rotating platform and configured to be rotated by the rotating platform, wherein a polishing surface of the polishing pad comprises a polishing region and a non-polishing region, the polishing region is configured to polish a semiconductor substrate, and the non-polishing region comprises a central region and an edge region far away from the central region;

a slurry provider configured to provide a slurry on the polishing pad; and

at least one detecting device disposed in the edge region of the non-polishing region of the polishing pad and configured to detect a composition and a corresponding concentration of the polishing slurry.

2. The polishing apparatus of claim 1, wherein the polishing pad comprises a recess, the detecting device is disposed in the recess, and an upper surface of the detecting device is aligned with a polishing surface of the polishing pad facing a semiconductor substrate.

3. The polishing apparatus of claim 1, wherein the polishing apparatus comprises two detection devices, the polishing region is between the central region and the edge region, one of the detection devices is disposed in the central region of the polishing pad, and the other is disposed in the edge region of the polishing pad.

4. A polishing apparatus, comprising:

a rotating platform;

a slurry provider configured to provide a slurry on the polishing pad; and

at least one detecting device disposed in the edge region of the non-polishing region of the polishing pad and configured to detect components and corresponding concentrations of the polishing slurry;

wherein the at least one detection device comprises a plurality of detection modules, and each detection module comprises:

a reaction zone configured to receive a polishing slurry on the polishing pad, the reaction zone including a reactive material corresponding to a component of the polishing slurry;

a detecting electrode configured to output a detecting signal when the component of the slurry reacts with the reactive substance; and

a processing chip configured to receive the detection signal to obtain a detection information including the composition and concentration of the slurry.

5. The polishing apparatus of claim 4, wherein the detection device further comprises a communication circuit configured to transmit the detection information to a monitoring device via wired or wireless transmission.

6. A method for polishing a semiconductor substrate, comprising:

providing a polishing slurry to a polishing surface on a polishing pad, wherein the polishing surface comprises a polishing region and a non-polishing region, wherein the non-polishing region comprises a central region and an edge region far away from the central region;

disposing a semiconductor substrate to the polishing region on the polishing surface for polishing; and

the components and concentration of the polishing slurry are detected by at least one detection device disposed in the polishing pad, wherein the at least one detection device is disposed in the edge region of the non-polishing region.

7. The method according to claim 6, wherein the step of detecting the composition and concentration of the polishing slurry further comprises:

detecting the components and initial concentration of the polishing slurry without polishing treatment by a detection device arranged at the center of the polishing pad; and

the composition and the polishing medium concentration of the polishing slurry in the polishing process are detected by another detecting device provided at the edge of the polishing pad.

8. The method of polishing a semiconductor substrate according to claim 7, further comprising:

providing the polishing slurry to the detecting device located at the center of the polishing pad before the polishing process; and

determining whether the initial concentration of the slurry is within a predetermined concentration range.

9. The method of polishing a semiconductor substrate according to claim 7, further comprising:

comparing the initial concentration of the slurry with the polishing medium concentration to obtain an attenuation ratio; and

when the attenuation ratio is larger than a preset attenuation ratio, a warning message is sent out.