JP2021079502A - CMP device - Google Patents

Abstract

To provide a CMP device which performs CMP polishing to a workpiece held by a dicing frame.SOLUTION: A CMP device 1 includes: an annular dicing frame 70 in which a dicing tape 71 for bonding a workpiece W is provided in a stretched manner; a holding mechanism 50 which is provided at a polishing head 10 and can hold the dicing frame 70; a movable mechanism 60 which may move the holding mechanism 50 up or down in a vertical direction; and a chuck 40 which is provided in the polishing head 10 at the inner side of the holding mechanism 50 and suctions and holds the workpiece W through the dicing tape 71.SELECTED DRAWING: Figure 3

Description

The present invention relates to a CMP apparatus for CMP polishing a work.

In the field of semiconductor manufacturing, a CMP apparatus for flattening a silicon wafer or the like (hereinafter referred to as “work”) is known.

The polishing apparatus described in Patent Document 1 is a polishing apparatus to which chemical mechanical polishing, so-called CMP (Chemical Mechanical Polishing) technology is applied. In this CMP apparatus, the work mounted on the polishing head is pressed against the platen to polish the work.

Japanese Unexamined Patent Publication No. 2016-159385

By the way, when transporting a thin work or the like, a dicing frame may be used in which the work is attached to a dicing tape to hold the work. The thickness of the dicing frame is about 10 to 20 mm, whereas the thickness of the work is about 0.7 mm.

When CMP polishing is performed without removing the work held by such a dicing frame from the dicing frame, there is a problem that the dicing frame interferes and CMP polishing cannot be performed.

Specifically, in the conventional CMP apparatus 100, as shown in FIG. 9, the polishing head 101 is provided so as to surround the head main body 102, the carrier 103 that rotates together with the head main body 102, and the carrier 103. It includes 104, an inner airbag 106 that pushes the carrier 103 toward the platen 105, and an outer airbag 107 that pushes the retainer ring 104 toward the platen 105. Further, compressed air is supplied to the air chamber 109 formed in the gap between the carrier 103 and the membrane sheet 108 held at the lower end of the retainer ring 104, and the work W is pressed against the platen 105 by the pressure of the compressed air. It is configured as follows.

However, in such a CMP apparatus 100, even if the dicing frame 110 is attached to the lower end of the polishing head 101 to polish the work W, the dicing frame 110 is sufficiently thicker than the work W, so that the work W becomes the platen 105. In addition to being unable to polish without contact, there is a problem that the dicing tape 111 to which the work W is attached is easily bent and cannot stably support the work W.

Therefore, a technical problem to be solved in order to perform CMP polishing on the work held in the dicing frame arises, and an object of the present invention is to solve this problem.

In order to achieve the above object, the CMP apparatus according to the present invention is a CMP apparatus that presses the surface of a work that is attracted and held by a polishing head against a platen to polish it, and a dicing tape to which the work is attached is stretched. An annular dicing frame provided, a holding mechanism provided on the polishing head capable of holding the dicing frame, a moving mechanism capable of raising and lowering the holding mechanism, and the polishing head provided inside the holding mechanism. It is provided with a chuck capable of sucking and holding the back surface of the work via the dicing tape.

According to this configuration, the back surface of the work is sucked and held in a state where the dicing tape is stretched and the front surface of the work is pushed downward from the lower surface of the dicing frame, so that the work can be polished without being removed from the dicing frame. it can. Further, since the back surface of the work is supported by the chuck, the work can be stably polished.

Further, in the CMP device according to the present invention, the moving mechanism can be expanded by compressed air, a base member connected to the holding mechanism, an elastic member that urges the base member in a direction away from the dicing frame, and compressed air. It is preferable to include an airbag that is provided and can push the base member in a direction approaching the dicing frame.

According to this configuration, when the airbag expands, the base member approaches the dicing frame against the elastic force of the elastic member, and when the airbag contracts, the base member separates from the dicing frame due to the elastic force of the elastic member. Since the movement mechanism is configured in, the dicing tape is stretched according to the expansion and contraction of the air bag, and the back surface of the work is sucked and held in a state where the front surface of the work is pushed downward from the lower surface of the dicing frame. Can be done.

Further, in the CMP device according to the present invention, the moving mechanism can be expanded by compressed air, a base member connected to the holding mechanism, an elastic member that urges the base member in a direction approaching the dicing frame, and compressed air. It is preferable that the base member is provided with an airbag that can be pulled up in a direction away from the dicing frame.

According to this configuration, when the airbag expands, the base member separates from the dicing frame against the elastic force of the elastic member, and when the airbag contracts, the base member approaches the dicing frame due to the elastic force of the elastic member. Since the movement mechanism is configured in, the dicing tape is stretched according to the expansion and contraction of the air bag, and the back surface of the work is sucked and held in a state where the front surface of the work is pushed downward from the lower surface of the dicing frame. Can be done.

Further, in order to achieve the above object, the CMP device according to the present invention is a CMP device that presses the surface of a work that is attracted and held by a polishing head against a platen to polish it, and is a dicing tape to which the work is attached. An annular dicing frame stretched with a dicing frame, a holding mechanism provided on the polishing head that can hold the dicing frame, a head moving mechanism that can raise and lower the polishing head, and the polishing inside the holding mechanism. A chuck provided on the head and capable of sucking and holding the back surface of the work via the dicing tape in a state in which the dicing tape is stretched when the holding mechanism holds the dicing frame is provided. There is.

According to this configuration, the back surface of the work is sucked and held in a state where the dicing tape is stretched and the front surface of the work is pushed downward from the lower surface of the dicing frame, so that the work can be polished without being removed from the dicing frame. it can. Further, since the back surface of the work is supported by the chuck, the work can be stably polished.

According to the present invention, polishing can be performed without removing the work from the dicing frame, and the work can be stably polished.

The perspective view which shows typically the CMP apparatus which concerns on 1st Embodiment of this invention. The vertical sectional view which shows the main part of a polishing head and a dicing frame schematically. The plan view which shows the dicing frame which holds a work. The schematic diagram which shows the procedure which performs CMP polishing after the polishing head of FIG. 2 holds a dicing frame. The vertical cross-sectional view which shows typically the main part of the polishing head and the dicing frame of the CMP apparatus which concerns on 2nd Embodiment of this invention. The schematic diagram which shows the procedure which performs CMP polishing after the polishing head of FIG. 5 holds a dicing frame. The vertical cross-sectional view which shows typically the main part of the polishing head and the dicing frame of the CMP apparatus which concerns on 3rd Embodiment of this invention. The schematic diagram which shows the procedure of performing CMP polishing after the polishing head of FIG. 7 holds a dicing frame. The schematic diagram which shows the state in the case of CMP polishing the work held in the dicing frame by the conventional CMP apparatus.

Each embodiment of the present invention will be described with reference to the drawings. In the following, when referring to the number, numerical value, quantity, range, etc. of components, it is limited to the specific number unless it is clearly stated or in principle it is clearly limited to the specific number. It is not a thing, and it may be more than or less than a specific number.

In addition, when referring to the shape and positional relationship of components, etc., unless otherwise specified or when it is considered that this is not the case in principle, those that are substantially similar to or similar to the shape, etc. shall be used. Including.

In addition, the drawings may be exaggerated by enlarging the characteristic parts in order to make the features easy to understand, and the dimensional ratios and the like of the components are not always the same as the actual ones. Further, in the cross-sectional view, hatching of some components may be omitted in order to make the cross-sectional structure of the components easy to understand.

[First Embodiment]
FIG. 1 is a perspective view schematically showing a CMP apparatus 1 according to the first embodiment of the present invention. The CMP apparatus 1 polishes one surface of the work W flatly. The CMP device 1 includes a platen 2 and a polishing head 10.

The platen 2 is formed in a disk shape and is connected to a rotation shaft 3 arranged below the platen 2. When the rotating shaft 3 is rotated by the drive of the motor 4, the platen 2 rotates in the direction of the arrow D1 in FIG. A polishing pad 5 is attached to the upper surface of the platen 2, and a CMP slurry which is a mixture of an abrasive and a chemical is supplied from a nozzle (not shown) on the polishing pad 5.

The polishing head 10 is formed to have a diameter smaller than that of the platen 2, and is connected to a rotating shaft 10a arranged above the polishing head 10. The polishing head 10 rotates in the direction of the arrow D2 in FIG. 1 because the rotation shaft 10a is rotated by driving a motor (not shown). The polishing head 10 is configured to be movable in the vertical direction and the horizontal direction by a head moving mechanism (not shown). The polishing head 10 descends when polishing the work W and presses the work W against the polishing pad 5. The work W to be polished by the polishing head 10 is delivered while being held by the dicing frame 70, which will be described later.

The operation of the CMP device 1 is controlled by a control means (not shown). The control means controls each of the components constituting the CMP device 1. The control means is, for example, a computer, and is composed of a CPU, a memory, and the like. The function of the control means may be realized by controlling with software, or may be realized by operating with hardware.

Next, the structure of the polishing head 10 will be described. FIG. 2 is a vertical cross-sectional view schematically showing a main part of the polishing head 10.

The polishing head 10 includes a head body 20 and a carrier 30.

The head body 20 is connected to the rotation shaft 10a and rotates together with the rotation shaft 10a. The head main body 20 is connected to a dense carrier 30 arranged below the head main body 20 via a rotating portion 21, and the head main body 20 and the carrier 30 rotate in conjunction with each other.

A carrier pressing means 31 is provided between the head body 20 and the carrier 30. The carrier pressing means 31 is an airbag or the like that is expanded by air supplied from a compressed air source (not shown). The pressure of the air supplied from the compressed air source is adjusted by a regulator (not shown). The carrier pressing means 31 presses the work W against the polishing pad 5 via the carrier 30 according to the pressure of the supplied air.

A chuck 40 is provided on the lower surface of the carrier 30. The chuck 40 includes a compact chuck base 41 and a porous chuck 42 made of a porous material housed in the chuck base 41. The lower surface (suction surface) 42a of the porous chuck 42 is formed to be substantially flat.

The porous chuck 42 is connected to a vacuum source and a compressed air source (not shown). The connection between the porous chuck 42 and the vacuum source and the connection between the porous chuck 42 and the compressed air source may be switched by using a switching valve or the like (not shown), or a pipe connecting the porous chuck 42 and the compressed air source. A conduit for connecting the path, the porous chuck 42, and the vacuum source may be prepared, and each conduit may be controlled to open and close as necessary.

The polishing head 10 includes a holding mechanism 50 and a moving mechanism 60.

The holding mechanism 50 is formed in a ring shape according to the shape of the dicing frame 70, which will be described later. A plurality of suction pads 51 are arranged on the lower surface of the holding mechanism 50 at substantially equal intervals.

The suction pad 51 is configured so that the suction and desorption of the dicing frame 70 can be arbitrarily switched. The suction pad 51 is, for example, a vacuum suction pad connected to a vacuum source (not shown). The shape of the suction pad 51 can be arbitrarily changed, and may be, for example, a flat type or a bellows type.

The moving mechanism 60 raises and lowers the holding mechanism 50 in the vertical direction. The moving mechanism 60 includes a base member 61, an elastic member 62, and an airbag 63.

The base member 61 is formed in a substantially columnar shape, and is arranged so as to surround the carrier 30. A holding mechanism 50 is provided on the lower surface of the base member 61.

The elastic member 62 and the airbag 63 are provided in a holder 64 fitted in the head body 20. The elastic members 62 and the airbag 63 are alternately arranged along the circumferential direction of the holder 64.

The elastic member 62 is a coil spring. The elastic member 62 is interposed between the holder 64 and the flange 66 of the hooking member 65 such as a bolt, the upper end thereof is joined to the flange 66, and the lower end is joined to the holder 64. The shaft portion 67 of the hooking member 65 penetrates the holder 64, and the tip thereof is joined to the base member 61. The elastic member 62 is inserted into the shaft portion 67 of the hooking member 65. As a result, the base member 61 is constantly lifted upward by the elastic force of the elastic member 62.

The airbag 63 is an airbag that can be expanded and contracted by air supplied from a compressed air source (not shown) connected via a conduit 68. The pressure of the air supplied from the compressed air source is adjusted by a regulator (not shown). The airbag 63 expands according to the pressure of the supplied air to move the base member 61 so as to push it downward. In the expanded state of the airbag 63, the lower end of the suction pad 51 is set to be located below the suction surface 42a.

As shown in FIG. 3, the work W is attached to the lower side of the dicing tape 71 stretched on the ring-shaped dicing frame 70. The dicing frame 70 is made of metal or resin. The thickness of the dicing frame 70 is set to about 1 to 2 mm. The dicing tape 71 is, for example, an ultraviolet curable tape or the like. The work W is a 6-inch substrate, and its thickness is about 0.7 mm. The work W may be a chip cut by a dicer, a chip laminated on the substrate, or the like, in addition to the thin and fragile substrate.

Next, a procedure for polishing using the CMP apparatus 1 according to the present embodiment will be described with reference to FIG.

First, as shown in FIG. 4A, the polishing head 10 is moved above the dicing frame 70 so that the suction pad 51 and the dicing frame 70 face each other.

Next, after the polishing head 10 is brought into contact with the dicing frame 70, as shown in FIG. 4B, air is supplied to the airbag 63 to expand it to resist the elastic force of the elastic member 62 and to resist the base member. The 61 is brought closer to the dicing frame 70, and the suction pad 51 is moved below the suction surface 42a. After that, the vacuum source connected to the suction pad 51 is activated, and the dicing frame 70 is sucked and held by the suction pad 51.

If the dicing frame 70 is sucked and held by the suction pad 51, the dicing frame 70 may be distorted due to the tension of the dicing tape 71. Therefore, by adopting, for example, a bellows type vacuum suction pad as the suction pad 51, the suction pad 51 can reliably suck the dicing frame 70 regardless of the presence or absence of distortion of the dicing frame 70.

When a lightweight and soft resin material is used for the dicing frame 70, the suction pad 51 can set the suction force for sucking the dicing frame 70 to be small, which simplifies the device of the suction pad 51. can do.

Further, by forming the dicing frame 70 thinly, the pushing amount of the airbag 63 (the stroke amount of the base member 61) becomes small, so that the configuration of the airbag 63 can be simplified.

In the state where the dicing frame 70 is sucked and held by the suction pad 51, the suction surface 42a is positioned so as to be arranged directly above the work W, and when the vacuum source of the porous chuck 42 is activated, the dicing tape 71 is released. The back surface W1 of the work W is adsorbed on the suction surface 42a via the work W.

Next, as shown in FIG. 4C, when the supply of air to the airbag 63 is stopped and the base member 61 is pulled upward by the elastic force of the elastic member 62, the porous chuck 42 is subjected to the dicing tape. The dicing tape 71 is extended by moving the suction pad 51 that sucks the dicing frame 70 while pressing the center of the 71, and the surface W2 of the work W is located slightly below the lower surface 70a of the dicing frame 70. doing.

Then, when the carrier pressing means 31 is activated to press the carrier 30, the work W is polished by pressing the front surface W2 of the work W against the polishing pad 5 with reference to the back surface W1 facing the porous chuck 42. ..

In this way, the CMP apparatus 1 according to the present embodiment sucks and holds the back surface W1 of the work W in a state where the dicing tape 71 is extended and the front surface W2 of the work W is pushed downward from the lower surface 70a of the dicing frame 70. As a result, polishing can be performed without removing the work W from the dicing frame 70. Further, since the back surface W1 of the work W is supported by the porous chuck 42, the work W can be stably polished.

[Second Embodiment]
Next, the CMP apparatus 1 according to the second embodiment of the present invention will be described. FIG. 5 is a vertical cross-sectional view schematically showing a main part of the polishing head 10 of the CMP apparatus according to the present embodiment. The CMP device 1 according to the present embodiment has the same configuration as the CMP device 1 according to the first embodiment described above, except for the moving mechanism. Therefore, among the configurations of the CMP apparatus 1 according to the present embodiment, the configurations common to the CMP apparatus 1 according to the first embodiment are designated by the same reference numerals and duplicated description will be omitted.

The moving mechanism 80 raises and lowers the holding mechanism 50 in the vertical direction. The moving mechanism 80 includes a base member 81, an elastic member 82, and an airbag 83.

The base member 81 is formed in a substantially columnar shape, and is arranged so as to surround the carrier 30. A holding mechanism 50 is provided on the lower surface of the base member 81.

The elastic member 82 and the airbag 83 are provided in a holder 84 fitted in the head body 20. The elastic members 82 and the airbag 83 are alternately arranged along the circumferential direction of the holder 84.

The elastic member 82 is a coil spring. The elastic member 82 is interposed between the base member 81 and the holder 84, and the upper end is joined to the holder 84 and the lower end is joined to the base member 81. The flange 86 functions as a retaining member for the hooking member 85 with respect to the holder 84. The shaft portion 87 penetrates the holder 84, and its tip is joined to the base member 81. The elastic member 82 is inserted into the shaft portion 87. As a result, the elastic force of the elastic member 82 urges the base member 81 away from the holder 84.

The airbag 83 is an airbag that can be expanded and contracted by air supplied from a compressed air source (not shown) connected via a conduit 88. The pressure of the air supplied from the compressed air source is adjusted by a regulator (not shown). The airbag 83 expands in response to the pressure of the supplied air, so that the flange 86 connected to the base member 81 can be pushed upward to lift the base member 81 upward. When the airbag 83 is not inflated, the lower end of the suction pad 51 is set to be located below the suction surface 42a.

Next, a procedure for polishing using the CMP apparatus 1 according to the present embodiment will be described with reference to FIG.

First, as shown in FIG. 6A, the polishing head 10 is moved above the dicing frame 70 so that the suction pad 51 and the dicing frame 70 face each other. At this time, no air is supplied to the airbag 83, and the base member 81 is urged downward by the elastic force of the elastic member 82.

Next, after the polishing head 10 is brought into contact with the dicing frame 70, as shown in FIG. 6B, the vacuum source connected to the suction pad 51 is activated, and the dicing frame 70 is sucked and held by the suction pad 51. To.

In the state where the dicing frame 70 is sucked and held by the suction pad 51, the suction surface 42a is positioned so as to be arranged directly above the work W, and when the vacuum source of the porous chuck 42 is activated, the dicing tape 71 is released. The work W is attracted to the suction surface 42a via the work W. As a result, the work W is attracted to the suction surface 42a substantially flatly with reference to the back surface W1.

Next, as shown in FIG. 6C, air is supplied to the airbag 83, the airbag 83 expands, and the flange 86 is pushed up, so that the base member 81 resists the elastic force of the elastic member 82. It has been pulled up. Then, the dicing tape 71 is extended by moving the suction pad 51 that sucks the dicing frame 70 upward while the porous chuck 42 holds the center of the dicing tape 71, and the surface W2 of the work W is the surface W2 of the dicing frame 70. It is located slightly below the lower surface 70a.

Then, when the carrier pressing means 31 is activated to press the carrier 30, the work W is polished by pressing the front surface W2 of the work W against the polishing pad 5 with reference to the back surface W1 facing the porous chuck 42. ..

In this way, the CMP apparatus 1 according to the present embodiment sucks and holds the back surface W1 of the work W in a state where the dicing tape 71 is extended and the front surface W2 of the work W is pushed downward from the lower surface 70a of the dicing frame 70. As a result, polishing can be performed without removing the work W from the dicing frame 70. Further, since the back surface W1 of the work W is supported by the porous chuck 42, the work W can be stably polished.

[Third Embodiment]
Next, the CMP apparatus 1 according to the third embodiment of the present invention will be described. FIG. 7 is a vertical cross-sectional view schematically showing a main part of the polishing head 10 of the CMP apparatus 1 according to the present embodiment. The CMP device 1 according to the present embodiment has the same configuration as the CMP device 1 according to the first embodiment described above, except that the moving mechanism is omitted. Therefore, among the configurations of the CMP apparatus 1 according to the present embodiment, the configurations common to the CMP apparatus 1 according to the first embodiment are designated by the same reference numerals and duplicated description will be omitted.

The holding mechanism 50 is provided below the carrier 30 so as to surround the chuck 40. The lower end of the suction pad 51 is fixed at a position above the suction surface 42a. Specifically, as will be described later, the position of the suction pad 51 is such that the surface W2 of the work W is located below the lower surface 70a of the dicing frame 70 while the dicing frame 70 is sucked and held by the suction pad 51. Is set to.

The dicing frame 70 is placed on the transposition table 90. The work W transferred between the CMP device and another device such as a transfer device is temporarily placed on the transfer table 90. The transfer table 90 is formed in a ring shape, and the inner diameter of the transfer table 90 is set to be larger than the outer diameter of the chuck 40. The shape of the transposition table 90 is not limited to the ring shape.

Next, a procedure for polishing using the CMP apparatus 1 according to the present embodiment will be described with reference to FIG.

First, as shown in FIG. 8A, the polishing head 10 is moved above the dicing frame 70 so that the suction pad 51 and the dicing frame 70 placed on the transposition table 90 face each other.

Next, as shown in FIG. 8B, the polishing head 10 is lowered so that the suction surface 42a comes into contact with the work W via the dicing tape 71. After that, when the vacuum source of the porous chuck 42 is activated, the work W is attracted to the suction surface 42a via the dicing tape 71. As a result, the work W is attracted to the suction surface 42a substantially flatly with reference to the back surface W1.

Next, as shown in FIG. 8C, the polishing head 10 is further lowered while extending the dicing tape 71, and the suction pad 51 is brought into contact with the dicing frame 70. After that, the vacuum source connected to the suction pad 51 is activated, and the dicing frame 70 is sucked and held by the suction pad 51.

When the dicing frame 70 is sucked and held by the suction pad 51, the surface W2 of the work W is located below the lower surface 70a of the dicing frame 70.

Next, the polishing head 10 is moved onto the platen 2, and as shown in FIG. 8D, the carrier pressing means 31 is activated to press the carrier 30 while the work W is attracted and held by the porous chuck 42. By doing so, the work W is polished by pressing the front surface W2 of the work W against the polishing pad 5 with reference to the back surface W1 facing the porous chuck 42.

In this way, the CMP apparatus 1 according to the present embodiment sucks and holds the back surface W1 of the work W in a state where the dicing tape 71 is extended and the front surface W2 of the work W is pushed downward from the lower surface 70a of the dicing frame 70. As a result, polishing can be performed without removing the work W from the dicing frame 70. Further, since the back surface W1 of the work W is supported by the porous chuck 42, the work W can be stably polished.

Further, the present invention can be modified in various ways other than the above as long as it does not deviate from the spirit of the present invention, and it is natural that the present invention extends to the modified ones.

1: CMP device 2: Platen 3: Rotating shaft 4: Motor 5: Polishing pad 10: Polishing head 10a: Rotating shaft 20: Head body 30: Carrier 31: Carrier pressing means 40: Chuck 41: Chuck base 42: Porous chuck 42a : Suction surface 50: Holding mechanism 51: Suction pad 60: Moving mechanism 61, 81: Base member 62, 82: Elastic member 63, 83: Air bag 64, 84: Holder 65, 85: Hook member 66, 86: Flange 67, 87: Shaft 68, 88: Pipeline 70: Dicing frame 71: Dicing tape 90: Transfer table W: Work W1: Back side (of work) W2: Front side (of work)

Claims (4)

A CMP device that polishes the surface of a work that is attracted and held by a polishing head by pressing it against a platen.
An annular dicing frame to which the dicing tape to which the work is attached is attached, and
A holding mechanism provided on the polishing head and capable of holding the dicing frame,
A moving mechanism that can raise and lower the holding mechanism,
A chuck provided on the polishing head inside the holding mechanism and capable of sucking and holding the back surface of the work via the dicing tape.
A CMP device characterized by being equipped with. The moving mechanism
The base member connected to the holding mechanism and
An elastic member that urges the base member in a direction away from the dicing frame, and
An airbag that is inflatable with compressed air and can extrude the base member in a direction approaching the dicing frame.
The CMP apparatus according to claim 1, wherein the CMP apparatus is provided. The moving mechanism
The base member connected to the holding mechanism and
An elastic member that urges the base member in a direction approaching the dicing frame, and
An airbag that is inflatable with compressed air and can pull up the base member in a direction away from the dicing frame.
The CMP apparatus according to claim 1, wherein the CMP apparatus is provided. A CMP device that polishes the surface of a work that is attracted and held by a polishing head by pressing it against a platen.
An annular dicing frame to which the dicing tape to which the work is attached is attached, and
A holding mechanism provided on the polishing head and capable of holding the dicing frame,
A head moving mechanism that can raise and lower the polishing head,
The polishing head is provided inside the holding mechanism, and when the holding mechanism holds the dicing frame, the back surface of the work is sucked and held via the dicing tape in a state where the dicing tape is stretched. With possible chucks
A CMP device characterized by being equipped with.

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