JP2005347532A - Equipment and method for chemical mechanical polishing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide chemical mechanical polishing equipment wherein slurry does not invade into a course of detection light and does not give bad influence on the detection light, and to provide a chemical mechanical polish method. <P>SOLUTION: This CMP equipment is provided with a platen 101 on which a polishing pad 105 was stuck, and a wafer holding mechanism 108 which holds a wafer 107 so that the wafer is pushed against the polishing pad 105. The CMP equipment is also provided with a transparent unit and a photodetector. The transparent unit is provided with a transparent component 313 which is attached in the platen so as to be located in apertures 324, 325 of the platen, and a transparent plate 311 which has a profile which gets into a hole 318 of the polishing pad and is attached on the transparent component with acrylic adhesives so that an upper surface becomes almost the same surface with the upper surface of the polishing pad. The photodetector optically detects status of the surface of the wafer under polishing through the transparent component 313 and the transparent plate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a CMP apparatus and a CMP method for performing chemical mechanical polishing (CMP) on a surface of a previously formed layer on a wafer in a semiconductor manufacturing process.

  In recent years, in a semiconductor manufacturing process, chemical mechanical polishing (CMP) is performed on the surface of a wafer in the middle of a process using a CMP apparatus, which is described in Patent Documents 1 and 2, for example. First, a schematic configuration of a conventional CMP apparatus will be briefly described.

  In the CMP apparatus, polishing is performed by rotating the platen with the polishing pad attached thereto and supplying slurry to the polishing pad while pressing the wafer held by the wafer holding mechanism against the polishing pad. In CMP, an insulating film or a metal film layer formed on the surface of a wafer is polished. Therefore, it is necessary to accurately detect the thickness of the layer left on the surface and stop polishing. This is called end point detection.

  FIG. 1 is a diagram illustrating an end point detection method described in Patent Document 1. In FIG. As shown in FIG. 1, the platen 101 to which the polishing pad 105 is attached is rotated, and while the slurry is supplied onto the polishing pad 105, the wafer 107 held by the wafer holding mechanism 108 is pressed while rotating. Since the platen 101 and the polishing pad 105 are opaque, the thickness of the surface layer cannot be detected by observing the wafer being polished. Therefore, the platen 101 is provided with a groove 102, a through hole 103, and a transparent member 104 for preventing slurry leakage, and the polishing pad 105 is provided with a window 106. Further, a probe 109 and an optical cable 110 are provided at the positions shown in the figure. A light beam sent from the optical cable 110 is emitted from the probe 109 and applied to the surface of the wafer 107 being polished. When the platen 101 rotates, the state shown in the figure is obtained every rotation. At that time, the reflected light of the light beam on the surface of the wafer is collected by the probe 109 and sent to the analyzing apparatus via the optical cable 110 to be spectrally reflected. The ratio is calculated to detect the film thickness of the remaining layer.

  Patent Document 2 also discloses a method similar to the end point detection method described in Patent Document 1. In any case, since the platen and the polishing pad are opaque as described above, the method of optically detecting the state of the wafer surface during polishing is provided with a transparent hole in the platen and the polishing pad, and through the hole. The wafer surface is periodically observed and inspected.

  In the configuration of FIG. 1, since the transparent member 104 made of glass is used, there is a problem that the surface is destroyed when the transparent member 104 contacts the surface of the wafer 107 during polishing. Moreover, the polishing pad 105 is worn in accordance with the polishing, and the polishing pad 105 becomes gradually thinner. For this reason, the position of the upper surface of the transparent member 104 is made sufficiently lower than the position of the upper surface of the polishing pad 105, but the distance between the upper surface of the transparent member 104 and the surface of the wafer 107 is large, and there is a slurry in that portion. Therefore, there is a problem that it becomes difficult to detect the film thickness of the layer on the wafer surface.

  Therefore, US Pat. No. 6,045,439 provides a platen 101 by providing a transparent portion in a part of the polishing pad 105, providing an opening in the platen 101, and arranging the transparent part of the polishing pad 105 in accordance with the opening of the platen 101. The structure in which the surface of the wafer being polished can be observed through the opening and the transparent portion is described. The polishing pad 105 having such a transparent portion is commercially available.

  FIG. 2 is a diagram showing a cross section of the opening when such a polishing pad 105 is used. As illustrated, an opening 111 is provided in the platen 101. The polishing pad 105 has a transparent portion 112 made of a material close to the polishing pad 105. A double-sided tape 113 is bonded to the lower surface of the polishing pad 105 except for the transparent portion 112, and the transparent portion 112 is bonded to the opening 111. At the time of polishing, the wafer 107 is pressed onto the polishing pad 105. Since the slurry is supplied to the surface of the polishing pad 105 as described above, a slurry layer 110 is formed between the wafer 107 and the polishing pad 105. The

  In the configuration of FIG. 2, the film thickness of the surface layer of the wafer 112 can be optically detected through the opening 111 and the transparent portion 112 during polishing. Further, since the transparent portion 112 is made of a material close to the polishing pad 105, the surface of the wafer 107 is not damaged, and the transparent portion 112 becomes as thin as the polishing pad 105 in accordance with the polishing. Further, since the transparent portion 112 is formed integrally with the polishing pad 105, the slurry does not leak from the opening 111. However, the polishing pad 105 having the transparent portion 112 has a problem that it is expensive.

  Therefore, a method of detecting the film thickness of the layer on the surface of the wafer being polished without using such a polishing pad has been considered. FIGS. 3A and 3B are diagrams showing a cross section of the opening when this method is performed. FIG. 3A shows a cross section in a state where the polishing pad is attached, and FIG. 3B explains a method of attaching the polishing pad. As shown in the figure, a hole 124 including an opening is provided in the platen 101, and a transparent member 125 made of transparent plastic or the like is fixed to the platen 101 with screws 126 so as to be located inside the hole 124. The transparent member 125 is attached to the platen via an O-ring 127, and slurry does not leak from the opening. The upper surface of the transparent member 125 is set to be almost the same height as the upper surface of the platen 101.

  Then, the transparent plate 121 with the double-sided tape 122 attached to the back surface is attached to the upper surface portion of the transparent member 125. In the double-sided tape 122, a portion 123 through which the detection light passes is removed so as not to adversely affect the detection light. The double-sided tape 113 is attached to the back surface of the polishing pad 105 having the hole 128 corresponding to the transparent plate 121, and the polishing pad 105 is attached to the upper surface of the platen 101 so that the transparent plate 121 fits into the hole 128. The transparent plate 121 is made of a material that does not affect polishing even when used together with the polishing pad 105 for polishing. In general, the polishing pad 105 has a two-layer structure including an upper layer made of polyurethane and a lower layer made of foamed polyurethane. The transparent plate 121 is made of polyurethane, for example. The polishing pad 105 and the transparent plate 121 are attached to the platen 101 with a double-sided tape coated with a highly adhesive rubber adhesive. This is because when the polishing pad 105 and the transparent plate 121 are thinned by polishing, it is necessary to peel off the polishing pad 105 and the transparent plate 121 attached to the platen 101 and attach a new polishing pad 105 and the transparent plate 121. This is to prevent the slurry from entering the bonded portion during polishing.

  The structure of FIG. 3 is relatively low cost because it does not use a polishing pad having a transparent portion. Further, when the polishing pad 105 is pasted, if the hole 128 is fitted to the transparent plate 121 and pasted, the positioning is easier than the pasting of the polishing pad of FIG. is there.

JP-A-7-52032 Japanese Patent Laid-Open No. 7-235520 US Pat. No. 6,045,439

  As described above, it is necessary to prevent the portion 123 of the transparent plate 121 through which the detection light passes from being attached with the double-sided tape 122 so as not to adversely affect the detection light. For this reason, the double-sided tape 122 to be attached to the transparent plate 121 is attached to the transparent plate 121 after cutting out the portion indicated by the reference numeral 123 in advance.

  In the structure of FIG. 3, the hole 128 of the transparent plate 121 and the polishing pad 105 can be fitted, but a gap is inevitable between them. As described above, the double-sided tape 122 is affixed between the platen 101 of the transparent plate 121, and slurry enters from the gap, and further the slurry enters between the transparent member 125 and the transparent plate 121. The problem that occurred. If a slurry exists between the transparent member 125 and the transparent plate 121, it has an adverse effect such as scattering of detection light.

  If the area where the transparent plate 121 is bonded to the platen 101 is increased, the slurry is less likely to enter between the transparent member 125 and the transparent plate 121. However, in order to take this measure, it is necessary to enlarge the transparent plate 121, which causes a problem of adversely affecting polishing.

  In addition, the polishing pad 105 may have a diameter of 1 m or more, and it is quite difficult to align and apply the polishing pad 105 with the double-sided tape attached to the back surface in a limited space on the platen 101. is there. Therefore, when the polishing pad 105 is pasted, as described above, in the structure of FIG. 3, when the hole 128 is fitted on the transparent plate 121 and pasted, the position is larger than the pasting of the polishing pad of FIG. 2. There is an advantage that the alignment is easy. However, this is a case where the transparent plate 121 is accurately bonded to a predetermined position in a predetermined direction. If the position and orientation of the attached transparent plate 121 are shifted, the position of the polishing pad 105 and The azimuth | direction will shift | deviate and the problem that it cannot paste normally arises.

  The present invention has been made in view of such problems, and on the premise of a configuration in which a polishing pad having a transparent portion is not used, that is, a configuration in which a transparent plate is used, the first object is that the slurry is detected light. A chemical mechanical polishing apparatus and method that can penetrate a path and do not adversely affect detection light, and a second object is to provide a chemical mechanical polishing apparatus and method that can accurately arrange a transparent plate at a predetermined position and orientation. Is to realize.

  In order to achieve the first object, the chemical mechanical polishing apparatus and method according to the first aspect of the present invention is characterized by using an acrylic adhesive as an adhesive for bonding the transparent plate. Since the transparent plate needs to be replaced when it is worn, a strong rubber adhesive was used, but even if an acrylic adhesive is used, it can be removed relatively easily if a solvent is used. I understood. Since the acrylic adhesive has good transparency, no problem occurs even if it is used in the detection light path. Furthermore, it is advantageous because it has a higher ability to prevent slurry leakage than rubber adhesives. When attaching a transparent plate, a double-sided tape having an acrylic adhesive is used.

  When the transparent plate is attached with an acrylic adhesive, various structures are possible. First, a hole is made in the platen, and a transparent plate is attached to the platen with an acrylic adhesive so as to close the hole. Since acrylic adhesives have a high ability to prevent slurry leakage, this structure hardly leaks slurry.

  Moreover, you may make it use the double-sided tape which has an acrylic adhesive with the structure of FIG. In this case, since the acrylic adhesive has good transparency, it is possible to apply a double-sided tape between the transparent member and the transparent plate. Conventionally, the opposing surfaces of the transparent member and the transparent plate have been finished to have a smooth surface in order to prevent scattering of the detection light. However, when a double-sided tape having an acrylic adhesive is used, the acrylic adhesive is 2 Since the space between the two surfaces is filled, scattering of the detection light can be reduced even if the surface is not smooth. Thereby, the processing cost of components can be reduced.

  In order to achieve the second object, the chemical mechanical polishing apparatus and method according to the second aspect of the present invention are configured to attach and detach a transparent member to which a transparent plate is bonded to a platen. In order not to adversely affect the polishing, the transparent plate needs to be a thin plate having the same thickness as the polishing pad, and it is difficult to provide a mechanism for positioning the transparent plate on the platen surface. Therefore, in the second aspect of the present invention, the transparent plate is accurately positioned and bonded to the transparent member outside, and then the transparent member is attached to and detached from the platen. Since the transparent member does not need to be provided on the surface of the platen, it can be accurately positioned and attached to the platen. In the second aspect, an acrylic adhesive may be used to adhere the transparent plate to the transparent member, as in the first aspect.

  According to the first aspect of the present invention, since the slurry does not enter the detection light path, the detection light is not scattered by the slurry, and the wafer surface state such as end point detection is optically detected. The accuracy when doing is improved. Thereby, the yield of the CMP process is improved, and the cost of the semiconductor device can be reduced.

  According to the second aspect of the present invention, since the transparent plate is attached with an accurate position and orientation, the polishing pad can be attached accurately and easily, and the workability of the CMP process is improved.

  Embodiments of the present invention will be described below. However, since the structure is the same as the conventional chemical mechanical polishing apparatus and method (CMP apparatus and method) except for the transparent plate mounting structure, only the transparent plate mounting structure will be described here. .

  4A and 4B are diagrams showing a transparent plate mounting structure according to the first embodiment of the present invention, in which FIG. 4A shows a cross section of the transparent plate and the polishing pad attached, and FIG. 4B shows the polishing pad attached. The method of attaching is explained.

  As shown in FIG. 4, in the transparent plate mounting structure of the first embodiment, an opening 201 is provided in the platen 101. The opening 201 is provided at a position where the surface of the wafer can be observed by passing under the wafer being polished when the platen 101 rotates. The transparent plate 202 is made of a transparent material such as polyurethane and does not adversely affect the polishing even when used together with the polishing pad, and has a shape that is somewhat larger than the opening 201, that is, capable of closing the opening 201. The transparent plate 202 is attached to the upper surface of the platen 101 so as to close the opening 201 after the double-sided tape 203 having an acrylic adhesive is attached to the lower surface thereof. Then, a double-sided tape 113 having a rubber adhesive is attached to the lower surface of the polishing pad 105 having the hole 128 into which the transparent plate 202 is fitted, so that the transparent plate 202 is fitted into the hole 128 and the polishing pad 105 is attached to the platen 101. Paste on top.

  In the structure of FIG. 4, the transparent plate 202 only blocks the opening 201, but the slurry does not leak from the opening 201 because the acrylic adhesive bonds between the transparent plate 202 and the platen 101. . Further, the double-sided tape 203 exists on the lower surface of the transparent plate 202 through which the detection light passes, but the base of the double-sided tape 203 and the acrylic adhesive have good transparency, and thus do not adversely affect the detection light.

  When the transparent plate 202 and the polishing pad 105 are worn and thinned by polishing, the polishing pad 105 is peeled off as in the conventional case, and the transparent plate 202 is peeled off using a solvent.

  FIGS. 5A and 5B are diagrams showing a transparent plate mounting structure according to a second embodiment of the present invention, in which FIG. 5A shows a cross-section with a transparent plate and a polishing pad attached, and FIG. The method of attaching is explained. In the second embodiment, in order to bond the transparent plate 211 to the transparent member 125 and the upper surface of the platen 101, a double-sided tape 212 having an acrylic adhesive is used instead of a double-sided tape having a rubber adhesive. Unlike the conventional example shown in FIG. 3, the others are the same.

  In the structure of the second embodiment, the double-sided tape 212 exists in a portion where the detection light passes between the transparent plate 211 and the transparent member 125, but the base of the double-sided tape 203 and the acrylic adhesive have good transparency. Therefore, the detection light is not adversely affected. Further, the slurry does not enter between the transparent plate 211 and the transparent member 125.

  Further, in the conventional example shown in FIG. 3, the upper surface of the transparent member 125 and the lower surface of the transparent plate are smoothed so that the detection light is not scattered, and therefore the manufacturing cost is high. In the second embodiment, since the upper surface of the transparent member 125 and the lower surface of the transparent plate are bonded with a double-sided tape having an acrylic adhesive, even if their surfaces are not sufficiently smooth, they are filled with the acrylic adhesive. Therefore, the scattering of the detection light can be reduced.

  FIG. 6 is a diagram showing this effect. In the figure, the horizontal axis represents the roughness Ra of the upper surface of the transparent member 125 and the lower surface of the transparent plate, and the vertical axis represents the intensity of detection light obtained using the actual detection optical system as a relative value. The detected light intensity indicated by the limit level in the figure is a level necessary for detection. From this figure, in the configuration in which an air layer is provided between the upper surface of the transparent member 125 and the lower surface of the transparent plate in FIG. 3, the roughness Ra between the upper surface of the transparent member 125 and the lower surface of the transparent plate is 0.3 μm or less. Although necessary, in the second embodiment, it can be seen that a sufficient detection light level can be obtained even at 0.6 μm. Therefore, the processing cost of the transparent member 125 and the transparent plate can be reduced.

  7A and 7B are diagrams showing a transparent plate mounting structure according to a third embodiment of the present invention, in which FIG. 7A shows a cross-section with a transparent plate and a polishing pad attached, and FIG. 7B shows a polishing pad attached. The method of attaching is explained. In the structure of the third embodiment, with the transparent member 313 removed, the transparent plate 311 is accurately bonded to the transparent member 313 with a double-sided tape 312 having an acrylic adhesive. This adhesion is performed using, for example, an assembly jig. Then, the transparent member 313 is inserted into the openings 324 and 325 of the platen 101 from the lower side through the O-ring 315, and the screw 314 is passed through the hole 316 to be coupled to the screw hole 317. Since the transparent member 313 is positioned by being fitted into the hole 325, the transparent plate 311 can be arranged at an accurate position and in an accurate orientation. Thereafter, similarly, the polishing pad 105 to which the double-sided tape 113 having a rubber adhesive is attached is attached so that the transparent plate 311 fits into the hole 318 of the polishing pad.

  In the structure of the third embodiment, the slurry enters from between the transparent plate 311 and the hole 318 of the polishing pad, but it does not leak because of the O-ring 315. Further, since the transparent plate 311 and the transparent member 313 are bonded with a double-sided tape 312 having an acrylic adhesive, the slurry does not enter. As in the second embodiment, the lower surface of the transparent plate 311 and the upper surface of the transparent member 313 may be rough to some extent.

  8A and 8B are diagrams showing a transparent plate mounting structure according to a fourth embodiment of the present invention, in which FIG. 8A shows a cross-section with a transparent plate and a polishing pad attached, and FIG. 8B shows a polishing pad attached. The method of attaching is explained. In the third embodiment, the transparent member is attached from the lower side of the platen. However, in the fourth embodiment, the transparent member is attached from the upper side of the platen to improve the workability of attaching and detaching the transparent member.

  Openings 422 and 423 are provided in the platen 101. A metal mounting member 417 as shown in the figure is fixed in the opening of the platen 101 with a screw 418 through an O-ring 419. The attachment member 417 has openings 424 and 425 in the center so that detection light can pass therethrough. Further, a groove 421 into which the screw hole 420 and the rubber ring 416 are fitted is provided on the upper surface.

  The transparent member 414 has a shape as shown in the figure, and has holes 415 on both sides. The transparent plate 411 has holes 413 larger than the holes 415 on both sides. With the transparent member 414 removed, the transparent plate 411 is accurately bonded to the transparent member 414 with a double-sided tape 412 having an acrylic adhesive. Then, the transparent member 414 is inserted into the opening 425 of the mounting member 417 from the upper side through the rubber ring 416, and the screw 426 is inserted under the hole 413, and further passed through the hole 415 to be coupled to the screw hole 420. . Since the transparent member 414 is positioned by fitting into the opening 425, the transparent plate 411 can be arranged at an accurate position and in an accurate orientation. Thereafter, similarly, the polishing pad 105 to which the double-sided tape 113 having a rubber adhesive is attached is attached so that the transparent plate 411 fits into the hole 427 of the polishing pad.

  Although the attachment member 417 is used in the fourth embodiment, a structure corresponding to the attachment member 417 may be processed on the platen 101.

  In the fourth embodiment, the same effect as that of the third embodiment is obtained, and the workability is good because the transparent member 414 can be attached and detached from the upper side of the platen 101.

  In the fourth embodiment, the hole 413 exists in the transparent plate 411. However, if the hole is small enough to allow the screw 426 to pass therethrough, the polishing is not affected.

  In the third and fourth embodiments, a double-sided tape having an acrylic adhesive is used to bond the transparent plate to the transparent member. An adhesive method may be used, and the effect of attaching the transparent plate to an accurate position in an accurate orientation can be obtained regardless of the adhesive or the adhesive method.

  Although the embodiments of the present invention have been described above, the shape and material can be variously modified, and the features of the embodiments can be combined. Further, the method for optically detecting the state of the wafer surface during polishing is not limited, and any method may be used.

  As described above, according to the present invention, the CMP process can be accurately performed with good workability using a relatively inexpensive material, so that the throughput of the CMP process can be improved and the cost can be reduced. Further, since the yield is improved, the manufacturing cost of the semiconductor device can be reduced.

It is a figure which shows schematic structure of the prior art example of the CMP apparatus which detects the state of the wafer surface during grinding | polishing. It is a figure which shows the structural example of the conventional polishing pad for detecting the state of the wafer surface under grinding | polishing. It is a figure which shows the conventional structure which uses a transparent plate in order to detect the state of the wafer surface under grinding | polishing. It is a figure which shows the structure of the transparent plate part of the CMP apparatus of 1st Example of this invention. It is a figure which shows the structure of the transparent plate part of the CMP apparatus of 2nd Example of this invention. It is a figure explaining an effect in the 2nd example. It is a figure which shows the structure of the transparent plate part of the CMP apparatus of 3rd Example of this invention. It is a figure which shows the structure of the transparent plate part of the CMP apparatus of 4th Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Platen 105 ... Polishing pad 113 ... Double-sided tape 201 ... Opening 202 ... Transparent plate 203 ... Double-sided tape which has acrylic adhesive

Claims (18)

A polishing pad is attached to the surface, and a platen that rotates during polishing.
A chemical mechanical polishing apparatus comprising a wafer holding mechanism for holding the wafer so as to press against the polishing pad while rotating during polishing, and polishing the wafer,
The platen comprises an opening that passes under the wafer as it rotates,
The polishing pad includes a hole at a position corresponding to the opening,
The chemical mechanical polishing apparatus is
A transparent plate having a shape that fits into the hole of the polishing pad and substantially the same thickness as the polishing pad, and is bonded to the platen with an acrylic adhesive so as to close the opening of the platen;
A chemical mechanical polishing apparatus comprising: a photodetector for optically detecting a state of the surface of the wafer being polished through the opening of the platen and the transparent plate. A polishing pad is attached to the surface, and a platen that rotates during polishing.
A chemical mechanical polishing apparatus comprising a wafer holding mechanism that holds the wafer against the polishing pad while rotating during polishing, and polishing the wafer,
The platen comprises an opening that passes under the wafer as it rotates,
The polishing pad includes a hole at a position corresponding to the opening,
The chemical mechanical polishing apparatus is
A transparent member provided in the opening of the platen and having an upper surface substantially the same as the upper surface of the platen;
A transparent plate having a shape that fits into the hole of the polishing pad and substantially the same thickness as the polishing pad, and is bonded to the upper surface of the transparent member with an acrylic adhesive;
A chemical mechanical polishing apparatus comprising: a photodetector for optically detecting the state of the surface of the wafer being polished through the transparent member and the transparent plate.   The chemical mechanical polishing apparatus according to claim 2, wherein the transparent member is attached to the platen via a leakage preventing member so that slurry supplied to the polishing pad during the polishing does not leak from the opening of the platen.   The chemical mechanical polishing apparatus according to claim 2 or 3, wherein the transparent plate is also bonded to the periphery of the opening on the upper surface of the platen with an acrylic adhesive. A polishing pad is attached to the surface, and a platen that rotates during polishing.
A chemical mechanical polishing apparatus comprising a wafer holding mechanism that holds the wafer against the polishing pad while rotating during polishing, and polishing the wafer,
The platen comprises an opening that passes under the wafer as it rotates,
The polishing pad includes a hole at a position corresponding to the opening,
The chemical mechanical polishing apparatus is
A transparent member attached to the platen so as to be positioned in the opening of the platen, and a shape that fits into the hole of the polishing pad, and the transparent surface is substantially the same as the upper surface of the polishing pad. A transparent unit having a transparent plate bonded to the member;
A chemical mechanical polishing apparatus comprising: a photodetector for optically detecting the state of the surface of the wafer being polished through the transparent member and the transparent plate.   The chemical mechanical polishing apparatus according to claim 5, wherein the transparent plate is bonded to the transparent member with an acrylic adhesive.   The chemical mechanical polishing apparatus according to claim 5 or 6, wherein the transparent unit is attached from a lower side of the platen.   The chemical mechanical polishing apparatus according to claim 5, wherein the transparent unit is attached from an upper side of the platen.   The said transparent unit is attached to the said platen via a leakage prevention member so that the slurry supplied to the said polishing pad may not leak from the opening of the said platen at the time of grinding | polishing. Chemical mechanical polishing equipment. A chemical mechanical polishing method in which a wafer is pressed against a polishing pad affixed to the surface of a rotating platen and polished.
The platen comprises an opening that passes under the wafer as it rotates,
The polishing pad includes a hole at a position corresponding to the opening,
A transparent plate having a shape that fits into the hole of the polishing pad and substantially the same thickness as the polishing pad is bonded to the platen with an acrylic adhesive so as to close the opening of the platen,
Optically detecting the state of the surface of the wafer being polished through the platen opening and the transparent plate;
A chemical mechanical polishing method, wherein polishing is stopped according to the detected surface state of the wafer. A chemical mechanical polishing method in which a wafer is pressed against a polishing pad affixed to the surface of a rotating platen and polished.
The platen comprises an opening that passes under the wafer as it rotates,
The polishing pad includes a hole at a position corresponding to the opening,
A transparent member having an upper surface substantially the same as the upper surface of the platen is disposed in the opening of the platen,
A transparent plate having a shape that fits into the hole of the polishing pad and substantially the same thickness as the polishing pad is bonded to the upper surface of the transparent member with an acrylic adhesive,
Optically detecting the state of the surface of the wafer being polished through the transparent member and the transparent plate,
A chemical mechanical polishing method, wherein polishing is stopped according to the detected surface state of the wafer.   The chemical mechanical polishing method according to claim 11, wherein the transparent member is attached to the platen via a leakage prevention member so that slurry supplied to the polishing pad during polishing does not leak from the opening of the platen.   The chemical mechanical polishing method according to claim 11 or 12, wherein the transparent plate is also adhered to the periphery of the opening on the upper surface of the platen with an acrylic adhesive. A chemical mechanical polishing method in which a wafer is pressed against a polishing pad affixed to the surface of a rotating platen and polished.
The platen comprises an opening that passes under the wafer as it rotates,
The polishing pad includes a hole at a position corresponding to the opening,
A transparent member to which a transparent plate having a shape that fits into the hole of the polishing pad is bonded, the transparent member is located in the opening of the platen, and the upper surface of the transparent plate is substantially the same as the upper surface of the polishing pad. Attach to the platen so that
Optically detecting the state of the surface of the wafer being polished through the transparent member and the transparent plate,
A chemical mechanical polishing method, wherein polishing is stopped according to the detected surface state of the wafer.   The chemical mechanical polishing method according to claim 14, wherein the transparent plate is bonded to the transparent member with an acrylic adhesive.   The chemical mechanical polishing method according to claim 14, wherein the transparent member is attached from a lower side of the platen.   The chemical mechanical polishing method according to claim 14, wherein the transparent member is attached from above the platen.   The said transparent member is attached to the said platen via a leak prevention member so that the slurry supplied to the said polishing pad may not leak from the opening of the said platen at the time of grinding | polishing. Chemical mechanical polishing method.

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