SEMICONDUCTOR MANUFACTURING DEVICE

A semiconductor manufacturing device includes: a turntable configured to be rotatable and having a first surface; a polishing pad provided on the first surface; a first support portion configured to rotatably hold the turntable; a top ring having a second surface and including a suction mechanism that holds an object to be processed on the second surface; a second support portion configured to rotatably hold the top ring; a first member to come into contact with the turntable or top ring; a second member to come into contact with the polishing pad or suction mechanism and with the turntable or top ring via the first member; and a first AE sensor to come into contact with the second member.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2022-039794, filed Mar. 15, 2022, the entire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a semiconductor manufacturing device.

BACKGROUND

When a surface of a wafer is to be polished, a polishing end point of a film is detected by a predetermined method. In a semiconductor manufacturing process, the accuracy required for polishing is increasing.

DETAILED DESCRIPTION

At least one embodiment provides a semiconductor manufacturing device capable of accurately determining a polishing end point.

In general, according to at least one embodiment, the semiconductor manufacturing device includes: a turntable configured to be rotatable and having a first surface; a polishing pad provided on the first surface; a first support portion configured to rotatably hold the turntable; a top ring having a second surface and including a suction mechanism that holds an object to be processed on the second surface; a second support portion configured to rotatably hold the top ring; a first member to come into contact with the turntable or top ring; a second member to come into contact with the polishing pad or suction mechanism and with the turntable or top ring via the first member; and a first AE sensor to come into contact with the second member.

Hereinafter, embodiments will be described with reference to the drawings. In the drawings, the same or similar parts are designated by the same or similar reference numerals.

First Embodiment

A semiconductor manufacturing device according to at least one embodiment includes: a turntable configured to be rotatable and having a first surface; a polishing pad provided on the first surface; a first support portion configured to rotatably hold the turntable; a top ring having a second surface and including a suction mechanism that holds an object to be processed on the second surface; a second support portion configured to rotatably hold the top ring; a first member to come into contact with the turntable; a second member to come into contact with the polishing pad or suction mechanism and with the turntable via the first member; and a first AE sensor to come into contact with the second member.

In the semiconductor manufacturing device of at least one embodiment, the first member, the second member, and the first AE sensor are provided on the turntable.

FIG.1is a schematic view of a semiconductor manufacturing device100according to at least one embodiment.FIG.2is a schematic view for illustrating an example of a polishing end point of a film.FIG.3is a schematic cross-sectional view of a main part of the semiconductor manufacturing device100according to the present embodiment.

The semiconductor manufacturing device100of the present embodiment includes a first support portion2, a turntable6, an AE sensor8, a polishing pad10, a first member14, a second member16, a fastening member18, an anti-vibration mechanism20, a top ring32including a suction mechanism30, a second support portion34, a slurry supply nozzle50, and a device management system60.

The semiconductor manufacturing device100of the embodiment is, for example, a device including a chemical mechanical polishing (CMP) device for chemically and mechanically polishing a film M formed on a wafer W and a system for controlling such a CMP device. In the semiconductor manufacturing device100of at least one embodiment, a plurality of CMP devices may be provided.

The wafer W is, for example, a semiconductor substrate. More specifically, the wafer W is, for example, a Si (silicon) substrate. The film M is formed on the surface of the wafer W. For example, the film M includes, as illustrated inFIG.2, a film M1and a film M2. The film M1is, for example, a silicon nitride (SiN) film. The film M2is, for example, a tetraethyl orthosilicate (TEOS) film.

For example, the semiconductor manufacturing device (CMP device)100removes the film M2by CMP processing so as to expose the film M1. In this case, for example, the film M2functions as a film to be polished, and the film M1functions as a stopper film. Ideally, the semiconductor manufacturing device (CMP device)100preferably ends the CMP processing when the removal of the film M2is completed. That is, it is preferable that an interface between the film M2as the film to be polished and the film M1as the stopper film is the polishing end point. The semiconductor manufacturing device100of at least one embodiment is used, for example, for determining such a polishing end point.

The configuration of the film M to which the semiconductor manufacturing device100of the embodiment is applied is not limited to the above case. For example, materials constituting the film M1and the film M2are not limited to those described above. Moreover, inFIG.2, the film M1is illustrated as being thicker than the film M2, but the actual dimensions are not limited to that case. Furthermore, inFIG.2, the wafer W, the film M1and the film M2are illustrated as having planar shapes, respectively, but the actual shapes are not limited to that case. For example, an interface between the wafer W and the film M1and the interface between the film M1and the film M2may be configured to have irregularities rather than being flat. Further, another film (not illustrated) may be provided between the film M1and the wafer W.

Here, a Z axis is defined. A Z direction parallel to the Z axis is, for example, a direction opposite to the vertical direction. The horizontal plane is, for example, a plane perpendicular to the Z axis.

The turntable6is a table that can be rotated, for example, in the horizontal plane by, for example, a motor (not illustrated).

The turntable6includes a first surface4. The first surface4is an upper surface of the turntable6. The first surface4is, for example, a surface parallel to the horizontal plane.

The polishing pad10is provided on the first surface4. The polishing pad10is used for polishing the film M. The polishing pad10is, for example, a pad made of polyurethane. However, the material of the polishing pad10is not limited to this case.

The slurry supply nozzle50is provided above the polishing pad10. The slurry supply nozzle50supplies slurry S used for polishing to the polishing pad10.

The first support portion2is provided under the turntable6. The first support portion2is connected to the turntable6. The first support portion2rotatably holds the turntable6. For example, the first support portion2is connected to a motor or the like (not illustrated). The first support portion2and the turntable6can be rotated in the horizontal plane by such a motor or the like.

The top ring32is provided above the turntable6. The top ring32includes a second surface32a. The second surface32ais a lower surface of the top ring32. The top ring32includes the suction mechanism30that holds the wafer W to be processed on the second surface32a. The suction mechanism30is a mechanism that holds the wafer W to be processed by, for example, suctioning gas between the wafer W and the suction mechanism30.

The second support portion34is provided above, for example, the top ring32. The second support portion34rotatably holds the top ring32. For example, the second support portion34is connected to a motor or the like (not illustrated). The second support portion34and the top ring32can be rotated in the horizontal plane by such a motor or the like.

The first member14is provided in the turntable6. The first member14is in contact with the turntable6. The first member14preferably contains a first insulating material having an electric conductivity of 10−6S/m or less.

For example, the turntable6includes a first recess part6bon a lower side of the turntable6. A third surface6c, which is an upper surface of the first recess part6b, is a surface facing the first surface4. For example, the third surface6cis a surface parallel to the horizontal plane. Nevertheless, the third surface6cdoes not have to be a surface parallel to the horizontal plane.

For example, the turntable6includes a second through hole6athrough which the third surface6cand the first surface4communicate with each other. A part of the first member14is provided in the second through hole6a. For example, an outer surface14aof the first member14and a side surface (inner side surface)6dof the second through hole6aare in contact with each other. Accordingly, the first member14and the turntable6are in contact with each other. The form of contact between the first member14and the turntable6is not limited to the above case.

The second member16is in contact with the polishing pad10. The second member16is also in contact with the turntable6via the first member14.

For example, the first member14includes a third through hole14b.

For example, the second member16includes a first portion16aand a second portion16bprovided above the first portion16aand having a diameter smaller than the diameter of the first portion16a.

For example, an inner side surface14cof the third through hole14bis in contact with the second portion16b. In this way, the second member16is in contact with the first member14. The second member16is in contact with the turntable6via the first member14.

For example, the second portion16bof the second member16is in contact with the polishing pad10.

The second member16is made of, for example, metal. The second member16is formed of, for example, stainless used steel (SUS). A damping coefficient of the second member16is preferably 0.3 dB/(MHz·cm) or less.

The second member16is fixed to the turntable6with the fastening member18. For example, the fastening member18fixes, for example, the first portion16aof the second member16to the third surface6cof the turntable6. The fastening member18is, for example, a bolt. However, the fastening member18may be a rivet, for example. The fastening member18includes a second insulating material. Here, the second insulating material is, for example, fiber reinforced plastics (FRP), but is not limited thereto.

The acoustic emission (AE) sensor8(an example of the first AE sensor) is in contact with the second member16. The AE sensor8converts the vibration generated in the wafer W by polishing the wafer W into an electric signal via the polishing pad10and the second member16and measures the electric signal. For example, the electrical signal measured by the AE sensor8changes when the removal of the film M2as the film to be polished is completed. At this stage, the semiconductor manufacturing device100finishes the polishing.

The anti-vibration mechanism20includes a first through hole20athrough which the fastening member18penetrates. The anti-vibration mechanism20is provided, for example, between the third surface6cof the turntable6and the first portion16aof the second member16. In this way, the anti-vibration mechanism20is fixed between the third surface6cand the first portion16aby the fastening member18penetrating the first through hole20a. The anti-vibration mechanism20includes, for example, rubber. Here, as the rubber, one kind or a combination of two or more kinds of natural rubber, synthetic rubber, silicone rubber, urethane rubber and sponge rubber is preferably used. The type of the material used for the anti-vibration mechanism20is not limited to the above case.

It is preferable that the AE sensor8is in contact with the second member16provided in the first recess part6bprovided in the turntable6.

The device management system60controls the polishing process by controlling rotation speeds of the first support portion2and the second support portion34, controlling an amount of slurry S dropped from the slurry supply nozzle50, and the like. The device management system60also measures and analyzes a signal measured by the AE sensor8. The device management system60may be implemented by an electronic circuit, or may be implemented by combining hardware such as a computer and software such as a program.

FIG.4is a schematic top view of the main part of the semiconductor manufacturing device100according to at least one embodiment. The first surface4aof the turntable6, the first member14, and the second member16are illustrated. InFIG.4, the polishing pad10, the top ring32, and other members are not illustrated.

Next, the operation and effect of the semiconductor manufacturing device according to at least one embodiment will be described.

FIG.5is a schematic cross-sectional view of a main part of a semiconductor manufacturing device1000according to a comparative embodiment of the embodiment. The AE sensor8is in contact with the third surface6cof the first recess part6bof the turntable6.

As described above, the AE sensor8converts the vibration generated by polishing the wafer W into an electric signal and measures the electric signal. Here, the turntable6is often formed of a metal member (conductive member) such as SUS. There is a problem where, when a control signal or the like of the motor or the like reaches the AE sensor8as noise via such a metal member (conductive member), an S/N ratio of the electric signal generated by polishing the wafer W deteriorates, and the polishing end point may be erroneously detected.

Thus, the semiconductor manufacturing device100of at least one embodiment includes the first member14in contact with the turntable6. The semiconductor manufacturing device100further includes the second member16in contact with the polishing pad10and also in contact with the turntable6via the first member14. Thus, the AE sensor8is in contact with the second member16.

The second member16is in contact with the polishing pad10. Accordingly, the AE sensor8can measure, via the second member16, the vibration generated by polishing the wafer W. The second member16is in contact with the turntable6via the first member14. In other words, the second member16is not in direct contact with the turntable6. As a result, the first member14hinders the arrival of the control signal or the like of the motor or the like to the AE sensor8via the turntable6. This makes it possible to provide a semiconductor manufacturing device capable of accurately determining the polishing end point.

The first member14preferably contains a first insulating material having an electric conductivity of 10−6S/m or less. The control signal or the like of the motor or the like is transmitted to the AE sensor8as electrical noise. Thus, when the first member14contains the above-mentioned insulating material, it is possible to hinder the transmission of the control signal or the like of the motor or the like.

The damping coefficient of the second member16is preferably 0.3 dB/(MHz·cm) or less. The second member16is required to transmit the vibration generated by polishing the wafer W to the AE sensor8via the polishing pad. When the damping coefficient is 0.3 dB/(MHz·cm) or less, the vibration generated by polishing the wafer W can be sufficiently transmitted to the AE sensor8.

It is preferable that the second member16is fixed to the turntable6by the fastening member18including the second insulating material. Since the fastening member18contains the second insulating material, the transmission of the control signal or the like of the motor or the like from the turntable6to the second member16can be hindered.

The anti-vibration mechanism20containing rubber and having the first through hole20athrough which the fastening member18penetrates is provided, so that it is possible to hinder the vibration of the turntable6from being transmitted to the AE sensor8.

It is preferable that the turntable6includes the third surface6cfacing the first surface4and the second through hole6athrough which the third surface6cand the first surface4communicate with each other, a part of the first member14is provided in the second through hole6a, and the second member16is in contact with the polishing pad10via the third through hole14bof the first member14. According to such an arrangement, it is possible to provide a semiconductor manufacturing device capable of accurately determining the polishing end point by hindering the transmission of the control signal or the like of the motor or the like.

It is preferable that the AE sensor8is in contact with the second member16provided in the first recess part6bprovided in the turntable6. The vibration accompanying the polishing of the wafer W can be efficiently transmitted to the AE sensor by providing the first recess part6bto reduce the thickness of the turntable6in the vicinity of the AE sensor8.

According to the semiconductor manufacturing device of at least one embodiment, it is possible to provide a semiconductor manufacturing device capable of accurately determining a polishing end point.

Second Embodiment

A semiconductor manufacturing device according to the present embodiment includes: a turntable configured to be rotatable and having a first surface; a polishing pad provided on the first surface; a first support portion configured to rotatably hold the turntable; a top ring having a second surface and including a suction mechanism that holds an object to be processed on the second surface; a second support portion configured to rotatably hold the top ring; a first member to come into contact with the top ring; a second member to come into contact with the suction mechanism and with the top ring via the first member; and a first AE sensor to come into contact with the second member.

In the semiconductor manufacturing device of the present embodiment, the first member, the second member, and the first AE sensor are provided on the top ring. Here, the description of the same content with those of the first embodiment is omitted.

FIG.6is a schematic view of a semiconductor manufacturing device110according to the present embodiment. The AE sensor (an example of the first AE sensor)8is provided on the top ring32.

FIG.7is a schematic cross-sectional view of a main part of the semiconductor manufacturing device110according to the present embodiment. The first member14is provided on the top ring32. The first member14is in contact with the top ring32.

For example, the top ring32includes a second recess part32b. A fourth surface32c, which is a lower surface of the second recess part32b, is a surface facing the second surface32a. For example, the fourth surface32cis a surface parallel to the horizontal plane. Nevertheless, the fourth surface32cdoes not have to be a surface parallel to the horizontal plane.

For example, the top ring32includes a fourth through hole32ethrough which the fourth surface32cand the second surface32acommunicate with each other. A part of the first member14is provided in the fourth through hole32e. For example, an outer surface14aof the first member14and a side surface (inner side surface)32dof the fourth through hole32eare in contact with each other. Accordingly, the first member14and the top ring32are in contact with each other. The form of contact between the first member14and the top ring32is not limited to the above case.

The second member16is in contact with the suction mechanism30. The second member16is in contact with the top ring32via the first member14.

For example, the first member14includes a third through hole14b.

For example, the second member16includes the first portion16aand the second portion16bprovided under the first portion16aand having a diameter smaller than the diameter of the first portion16a.

For example, the inner side surface14cof the third through hole14bis in contact with the second portion16b. In this way, the second member16is in contact with the first member14. The second member16is in contact with the top ring32via the first member14.

Further, for example, the second portion16bof the second member16is in contact with the suction mechanism30via the third through hole14b.

The second member16is fixed to the top ring32with the fastening member18. For example, the fastening member18fixes the first portion16aof the second member16to the fourth surface32cof the top ring32.

The acoustic emission (AE) sensor8(an example of the first AE sensor) is in contact with the second member16. The AE sensor8converts the vibration generated in the wafer W by polishing the wafer W into an electric signal via the suction mechanism30and the second member16and measures the electric signal.

The anti-vibration mechanism20includes a first through hole20athrough which the fastening member18penetrates. The anti-vibration mechanism20is provided, for example, between the fourth surface32cof the top ring32and the first portion16aof the second member16. In this way, the anti-vibration mechanism20is fixed between the fourth surface32cand the first portion16aby the fastening member18penetrating the first through hole20a.

FIG.8is a schematic bottom view of the semiconductor manufacturing device110according to the present embodiment.FIG.8is a diagram schematically illustrating the positional relationship between the turntable6, the top ring32, the first member14, and the second member16. InFIG.8, the polishing pad10, the top ring32, and other members are not illustrated.

The AE sensor8may be provided on the top ring32as in the embodiment, or may be provided on the turntable6as in the first embodiment.

When the AE sensor8is provided on the turntable6, the signal generated from the wafer W is measured via the polishing pad10. The polishing pad10is made of polyurethane, for example. Thus, it is considered that the damping coefficient of the polishing pad10is larger than the damping coefficient of the metal member or the like. On the other hand, when the AE sensor8is provided on the top ring32, the signal generated from the wafer W is measured via the suction mechanism30. The suction mechanism30is formed of a metal such as SUS. Accordingly, it is considered that the damping coefficient of the suction mechanism30is relatively small. Thus, from this point of view, it is preferable to provide the AE sensor8on the top ring32.

Next, the operation and effect of the semiconductor manufacturing device of the present embodiment will be described.

In the semiconductor manufacturing device110, the second member16is in contact with the suction mechanism30. Accordingly, the AE sensor8can measure, via the second member16, the vibration generated by polishing the wafer W. The second member16is in contact with the top ring32via the first member14. In other words, the second member16is not in direct contact with the top ring32. As a result, the first member14hinders the arrival of the control signal or the like of the motor or the like to the AE sensor8via the top ring32. This makes it possible to provide a semiconductor manufacturing device capable of accurately determining the polishing end point.

It is preferable that the second member16is fixed to the top ring32by the fastening member18including the second insulating material. Since the fastening member18contains the second insulating material, the transmission of the control signal or the like of the motor or the like from the top ring32to the second member16can be hindered.

The anti-vibration mechanism20containing rubber and having the first through hole20athrough which the fastening member18penetrates is provided, so that it is possible to hinder the vibration of the top ring32from being transmitted to the AE sensor8.

It is preferable that the top ring32includes the fourth surface32cfacing the second surface32aand the fourth through hole32ethrough which the second surface32aand the fourth surface32ccommunicate with each other, a part of the first member14is provided in the fourth through hole32e, and the second member16is in contact with the suction mechanism30via the third through hole14bof the first member14. According to such an aspect, it is possible to provide a semiconductor manufacturing device capable of accurately determining the polishing end point by hindering the transmission of the control signal or the like of the motor or the like.

It is preferable that the AE sensor8is in contact with the second member16provided in the second recess part32bprovided in the top ring32. The vibration accompanying the polishing of the wafer W can be efficiently transmitted to the AE sensor by providing the second recess part32bto reduce the thickness of the top ring32in the vicinity of the AE sensor8.

According to the semiconductor manufacturing device of the present embodiment, it is also possible to provide a semiconductor manufacturing device capable of accurately determining the polishing end point.

Third Embodiment

A semiconductor manufacturing device of the present embodiment is different from the semiconductor manufacturing device of the first embodiment in the feature of further including a third member to come into contact with the turntable, a fourth member to come into contact with the polishing pad and with the turntable via the third member, and a second AE sensor to come into contact with the fourth member. Here, the description of the same content with those of the first embodiment and the second embodiment is omitted.

FIG.9is a schematic top view of a main part of a semiconductor manufacturing device120according to the present embodiment.FIG.9is a diagram schematically illustrating the positional relationship between the first member14, the second member16, and the AE sensor8with respect to the turntable6. In the semiconductor manufacturing device120, a plurality of AE sensors8are provided on the turntable6.

The semiconductor manufacturing device120includes a plurality of first members including a first member14eand a first member14f(an example of the third member). The semiconductor manufacturing device120includes a plurality of second members including a second member16eand a second member16f(an example of the fourth member). The semiconductor manufacturing device120further includes a plurality of AE sensors including an AE sensor8a(an example of the first AE sensor) and an AE sensor8b(an example of the second AE sensor). This makes it possible to detect polishing end points at a plurality of locations of the wafer W. Thus, the detection accuracy of the polishing end point can be improved.

InFIG.9, the polishing pad10and other members are not illustrated.

In addition, inFIG.9, a rotation center axis O of the turntable6is provided between the first member14e, the second member16ealong with the AE sensor8a, and the first member14f, the second member16falong with the AE sensor8b. Nevertheless, the first member14f, the second member16falong with the AE sensor8bmay be provided between the rotation center axis O of the turntable6and the first member14e, the second member16ealong with the AE sensor8a.

Further, it is preferable that the distance between the rotation center axis O of the turntable6and the AE sensor8aand the distance between the rotation center axis O of the turntable6and the AE sensor8bin the plane parallel to the first surface4is different. This is because the different distances make it possible to measure polishing end points of a plurality of regions of the wafer W.

The distance between the rotation center axis O of the turntable6and the AE sensor8aand the distance between the rotation center axis O of the turntable6and the AE sensor8bin the plane parallel to the first surface4may be the same. This is because the number of measurements by the AE sensor8per unit time increases, so that the polishing end point can be measured more accurately.

According to the semiconductor manufacturing device of the present embodiment, it is also possible to provide a semiconductor manufacturing device capable of accurately determining the polishing end point.

Fourth Embodiment

A semiconductor manufacturing device of the present embodiment is different from the semiconductor manufacturing device of the second embodiment in the feature of further including a third member to come into contact with a top ring, a fourth member to come into contact with a suction mechanism and with the top ring via the third member, and a second AE sensor to come into contact with the fourth member. Here, the description of the same content with those of the semiconductor manufacturing devices according to the first to third embodiments is omitted.

FIG.10is a schematic top view of a main part of a semiconductor manufacturing device130according to the present embodiment.FIG.10is a diagram schematically illustrating the positional relationship between the first member14, the second member16, and the AE sensor8with respect to the turntable6and the top ring32. A rotation center axis OA of the turntable6and a rotation center axis OB of the top ring32are also illustrated. In the semiconductor manufacturing device130, a plurality of AE sensors8are provided on the top ring32.

InFIG.10, the polishing pad10, the suction mechanism30and other members are not illustrated.

According to the semiconductor manufacturing device of the present embodiment, it is also possible to provide a semiconductor manufacturing device capable of accurately determining the polishing end point.

Fifth Embodiment

A semiconductor manufacturing device of the present embodiment is different from the semiconductor manufacturing device of the first embodiment in the feature that a first member is in contact with a turntable, a second member is in contact with a polishing pad and with the turntable via the first member, and the semiconductor manufacturing device further includes a third member to come into contact with a top ring, a fourth member to come into contact with a suction mechanism and with the top ring via the third member, and a second AE sensor to come into contact with the fourth member. Here, the description of the same content with those of the semiconductor manufacturing devices according to the first to fourth embodiments is omitted.

FIG.11is a schematic view of a semiconductor manufacturing device140according to the present embodiment.FIG.11is a diagram schematically illustrating the positional relationship between the first member14, the second member16, and the AE sensor8with respect to the turntable6and the top ring32. The first member14e, the second member16e, and the AE sensor8aare provided on the turntable6. The first member14f(an example of the third member), the second member16f(an example of the fourth member), and the AE sensor8b(an example of the second AE sensor) are provided on the top ring32. The rotation center axis OA of the turntable6and the rotation center axis OB of the top ring32are illustrated inFIG.11.

InFIG.11, the polishing pad10, the suction mechanism30and other members are not illustrated.

Also according to the semiconductor manufacturing device of the present embodiment, it is possible to provide a semiconductor manufacturing device capable of accurately determining the polishing end point.

In the above embodiments, examples in which one AE sensor8or two AE sensors8are provided are described. However, the number of the AE sensors8in the semiconductor manufacturing device of the embodiments is, of course, not limited to one or two. In other words, in the semiconductor manufacturing device of the embodiments, three or more AE sensors8may be provided. For example, a time difference until the vibration of the wafer W reaches each of the three AE sensors is measured. Thus, it is possible to specify from which part of the wafer W the vibration is generated by using the time difference. In other words, it is possible to identify a point where the vibration of the wafer W is generated by using the time difference.