US20090318062A1

US20090318062A1 - Polishing pad and polishing device

Info

Publication number: US20090318062A1
Application number: US12/261,666
Authority: US
Inventors: Allen Chiu; Shao-Yu Chen; Yu-Lung Jeng
Original assignee: BESTAC ADVANCED MATERIAL Co Ltd
Current assignee: BESTAC ADVANCED MATERIAL Co Ltd
Priority date: 2008-06-19
Filing date: 2008-10-30
Publication date: 2009-12-24
Also published as: TWM347669U

Abstract

The present invention provides a polishing pad with a pressure sensor and the polishing apparatus thereof. The polishing pad is used in the polishing process of semiconductor and other work piece, which includes at least one substrate, at least one pressure sensor and at least one signal transmitting module. The substrate has a polishing face, a bottom face opposite to the polishing face, and at least one cavity set on the bottom face of the substrate. The pressure sensor is set in the cavity and configured for providing a pressure signal. The signal transmitting module is set on the polishing pad and configured for transmitting a pressure signal. The pressure signal is a loading pressure value and/or loading pressure distribution on the polishing pad with a preset range. Thus, with the pressure signal, the polishing apparatus prevents the concerned work piece from being over polished to further improve polishing quality and yield.

Description

BACKGROUND OF THE INVENTION

1. Technical Field
The present invention is related to a polishing pad, and particularly to a polishing pad with a pressure sensor and the polishing apparatus thereof.
2. Description of Related Art
Most of electric chips are consisted of various laminated layers with various materials. For example, semiconductor wafer (silicon wafer) is one of the various materials. For polarization or other destination, a polishing process or thinning process is necessary for the removal of excess laminated material when a new laminated layer is intended to be added. Such a polishing process is called chemical mechanical polishing (CMP). Many CMP steps may be necessary for the requirement of uniform surface for the addition of laminated layers.
However, with the advances of manufacture technology, the higher density the layout of conductive lines is, the more narrow the width of the conductive lines is. Thus, the tolerance of pressure error reduces because the pressure supplied by the polishing apparatus is only 1 PSI to 2 PSI. The pressure setting is one of important issues for the polishing process. Moreover, a polishing pad is generally sandwiched between the polishing apparatus and the concerned work piece. Thus, there is pressure bias between the preset pressure and an actual pressure.
Accordingly, the present invention provides a polishing pad with a pressure sensor and a polishing apparatus thereof. The pressure sensor is advantageous positioned to prevent the pressure sensor from being interfered and abraded by polishing chemicals. The pressure sensor directly detects the pressure loaded on a concerned work piece by the polishing apparatus and positively or passively transmits the pressure signal back. Thus, the drawbacks of over pressure or non-uniform distribution of pressure may be reduced to further the yield of the concerned polished work piece.

BRIEF SUMMARY OF THE INVENTION

Accordingly, the present invention provides a polishing pad with a pressure sensor. The polishing pad is used in the polishing process of semiconductor and other work piece, which includes at least one substrate, at least one pressure sensor and at least one signal transmitting module. The substrate has a polishing face, a bottom face opposite to the polishing face, and at least one cavity set on the bottom face of the substrate. The pressure sensor is set in the cavity and configured for providing a pressure signal. The signal transmitting module is set on the polishing pad and configured for transmitting a pressure signal. The pressure signal is a loading pressure value and/or loading pressure distribution on the polishing pad with a preset range. Thus, with the pressure signal, the polishing apparatus prevents the concerned work piece from being over polished to further improve polishing quality and yield.
One of objects of the present invention provides a polishing pad with a pressure sensor to detect pressure value and distribution during polishing process.
One of objects of the present invention provides a polishing pad with a pressure sensor to prevent a concerned work piece from over polishing and improve polishing quality and yield.
One of objects of the present invention provides a polishing pad with a pressure sensor to implement a preferred method of signal transmission and signal transmission in time.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The invention as well as a preferred mode of use, further objectives and advantages thereof will best be understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings, wherein:

FIG. 1 is a cross-sectional schematic diagram illustrating a polishing pad in accordance with one preferred embodiment of the present invention.

FIG. 2 is a cross-sectional schematic diagram illustrating a polishing pad in accordance with one preferred embodiment of the present invention.

FIG. 3 is a cross-sectional schematic diagram illustrating a signal transmitting module in according with one preferred embodiment of the present invention.

FIG. 4 is a cross-sectional schematic diagram illustrating another signal transmitting module in according with one preferred embodiment of the present invention.

FIG. 5 is a cross-sectional schematic diagram illustrating another signal transmitting module in according with one preferred embodiment of the present invention.

FIG. 6 is a cross-sectional schematic diagram illustrating another signal transmitting module in according with one preferred embodiment of the present invention.

FIG. 7 is a cross-sectional schematic diagram illustrating a polishing apparatus in according with one preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a polishing pad with a sensor. Some sensors or the detail process or manufacture of the polishing pad used are implemented by the current technology. Thus, some known description is not mentioned in following illustration. The sizes of components are not practical rather than for illustration.
FIG. 1 is a cross-sectional schematic diagram illustrating a polishing pad in accordance with one preferred embodiment of the present invention. The polishing pad 2 is used in the polishing process of semiconductor and other work piece, which includes at least one substrate 21, at least one pressure sensor 3 and at least one signal transmitting module (not shown in the figure). The substrate 21 has a polishing face 211, a bottom face 212 opposite to the polishing face 211, and at least one cavity 213 set on the bottom face 212 of the substrate 21. The pressure sensor 3 is set in the cavity 213 and configured for providing a pressure signal. The signal transmitting module is set on the polishing pad 2 and configured for transmitting a pressure signal. In one embodiment, the pressure signal is a loading pressure value and/or loading pressure distribution on the polishing pad 2 with a preset range. Thus, with the pressure signal, the polishing apparatus prevents the concerned work piece from being over polished to further improve polishing quality and yield. Next, in FIG. 2, the polishing pad 2 have more than the two substrates 21 and the pressure sensor 3 is sandwiched between the two substrates 21 to form a complex polishing pad.
FIG. 3 is a cross-sectional schematic diagram illustrating a signal transmitting module in according with one preferred embodiment of the present invention. The exemplary signal transmitting module includes a printed circuit board 31 (PCB) and couples a circuit 311 as a power supply for direct transmission.
FIG. 4 is a cross-sectional schematic diagram illustrating another signal transmitting module in according with one preferred embodiment of the present invention. The exemplary signal transmitting module includes at least one conductive line 32 as the power supply to positively transmit signal.
FIG. 5 is a cross-sectional schematic diagram illustrating another signal transmitting module in according with one preferred embodiment of the present invention. The exemplary signal transmitting module includes at least one battery of power supply 33 which may be button battery, Mercury battery, dry battery, alkaline battery, Lead/Acid Battery, Nickel-Cadmium Battery, Nickel-Metal hydride batteries, Secondary lithium battery, Li-ion Battery, polymer lithium battery, fuel battery and solar battery and used to positively transmit the signal.
FIG. 6 is a cross-sectional schematic diagram illustrating another signal transmitting module in according with one preferred embodiment of the present invention. The exemplary signal transmitting module includes at least one wireless signal emitter 34 to passively transmit the signal.
Another signal transmitting module in according with one preferred embodiment of the present invention is provided herein. The exemplary signal transmitting module is integrated with the pressure sensor 3 into a whole device (not shown in the figure). The whole device includes a chip, a controller, a wireless signal emitter and at least one a power supply. The frequency range of the wireless signal emitter is about from 100 MHz to 3 GHz. Furthermore, the power supply may be a vibrating motor device, external magnetic field motor device, or button battery, Mercury battery, dry battery, alkaline battery, Lead/Acid Battery, Nickel-Cadmium Battery, Nickel-Metal hydride batteries, Secondary lithium battery, Li-ion Battery, polymer lithium battery, fuel battery and solar battery, and so on. These configuration is a passive method of transmitting signal.
FIG. 7 is a cross-sectional schematic diagram illustrating a polishing apparatus in according with one preferred embodiment of the present invention. The polishing apparatus 4 is configured for polishing a work piece 5 and loading a polishing pad 2. The polishing pad 2 includes at least one substrate 21, at least one pressure sensor 3 and at least one first signal transmitting module (not shown in the figure). The substrate 21 includes a polishing face 211, a bottom face 212 opposite to the polishing face 211 and a cavity 213 set on the bottom face 212 of the substrate 21. The pressure sensor 3 is set in the cavity 213 and configured for providing a pressure signal. The first signal transmitting module is set on the polishing pad 2 and configured for transmitting the pressure signal. In one embodiment, the pressure signal is a loading pressure value and/or loading pressure distribution on the polishing pad 2 with a preset range. An alarm device 47 is configured for emitting an alarm signal on condition of the pressure signal out of the present range to stop the polishing apparatus 4.
Furthermore, the polishing apparatus 4 includes a first platform 41, a driving device 411, a second platform 42, a pressing device 43, at least one signal receiving module 44 and a display device 45. The polishing pad 2 is sealed with an adhesive 46 and fixed on the first platform 41. The adhesive 46 may be a pressure-sensitive adhesive. The first platform 41 is configured for loading the polishing pad 2 and coupling the bottom face 212 of the polishing pad 2. In one embodiment, the driving device 411 drives the first platform 41 to rotate. The second platform 42 is configured for loading the work piece 5. The pressing device 43 is configured for providing a pressure loaded between the polishing pad 2 of the first platform 41 and the work piece 5 of the second platform 42. The signal receiving module 44 is configured for receiving the pressure signal provided by the polishing pad 2. The signal receiving module 44 may be a wireless signal receiver 441. The display device 45 is configured for displaying the pressure signal.
Accordingly, a second signal transmitting module is configured for coupling with the first signal transmitting module of the polishing pad 2 and the signal receiving module 44 of the polishing apparatus 4. The second signal transmitting module may be a print circuit board (PCB) 31, a conductive line 32 or a connector. In one embodiment, the second signal transmitting module is set on a surface of the polishing pad 2 attached to the first platform 41.
Accordingly, the present invention provides a polishing pad with a pressure sensor and a polishing apparatus thereof. The pressure sensor is advantageous positioned to prevent the pressure sensor from being interfered and abraded by polishing chemicals. The pressure sensor directly detects the pressure loaded on a concerned work piece by the polishing apparatus and positively or passively transmits the pressure signal back. Thus, the drawbacks of over pressure or non-uniform distribution of pressure may be reduced to further the yield of the concerned polished work piece.
Although the present invention has been explained in relation to its preferred embodiment, it is to be understood that other modifications and variation can be made without departing the spirit and scope of the invention as hereafter claimed.

Claims

1. A polishing pad, applied to a polishing process of semiconductor or other work piece, said polishing pad comprising:

at least one substrate comprising a polishing face, a bottom face opposite to said polishing face, and at least one cavity set on said bottom face;

at least one pressure sensor set in said cavity and configured for providing a pressure signal; and

at least one signal transmitting module configured for transmitting said pressure signal.

2. The polishing pad according to claim 1, wherein said pressure signal from pressure sensor comprises a loading pressure value within a preset range.

3. The polishing pad according to claim 1, wherein said pressure signal from pressure sensor comprises a loading pressure distribution within a preset range.

4. The polishing pad according to claim 1, wherein said signal transmitting module comprises a print circuit board.

5. The polishing pad according to claim 1, wherein said signal transmitting module comprises at least one conductive line.

6. The polishing pad according to claim 1, wherein said signal transmitting module comprises a battery of power supply.

7. The polishing pad according to claim 1, wherein said signal transmitting module comprises a wireless signal emitter.

8. The polishing pad according to claim 1, wherein said pressure sensor and said signal transmitting module are integrated into a whole module which comprises a chip, a controller, a wireless signal emitter and a power device.

9. The polishing pad according to claim 1, wherein there are two said substrates and said pressure sensor sandwiched between said two substrates.

10. A polishing apparatus, configured for polishing a work piece and loading a polishing pad, wherein said polishing pad comprises a substrate, at least one pressure sensor and at least one first signal transmitting module; wherein said substrate comprises a polishing face, a bottom face opposite to said polishing face and a cavity set on said bottom face, and said pressure sensor is set in said cavity and configured for providing a pressure signal, and said first signal transmitting module is set on said polishing pad and configured for transmitting said pressure signal; said polishing apparatus comprising:

a first platform, configured for loading said polishing pad and coupling said bottom face of said polishing pad;

a driving device, configured for driving said first platform to rotate;

a second platform, configured for loading said work piece;

a pressing device, configured for providing a pressure loaded between said polishing pad of said first platform and said work piece of said second platform;

at least one signal receiving module, configured for receiving said pressure signal provided by said polishing pad; and

a display device, configured for displaying said pressure signal.

11. The polishing apparatus of claim 10, wherein said polishing pad is sealed with an adhesive and fixed on said first platform.

12. The polishing apparatus of claim 11, wherein said adhesive is a pressure-sensitive adhesive.

13. The polishing apparatus of claim 10, wherein said pressure signal from pressure sensor comprises a loading pressure value on said polishing pad within a preset range.

14. The polishing apparatus of claim 10, wherein said pressure signal from pressure sensor comprises a loading pressure distribution on said polishing pad within a preset range.

15. The polishing apparatus of claim 10, further comprising an alarm device configured for emitting an alarm signal on condition of said pressure signal out of said present range.

16. The polishing apparatus of claim 15, wherein said alarm device emits said alarm signal to stop said polishing apparatus.

17. The polishing apparatus of claim 10, further comprising a second signal transmitting module configured for coupling with said first signal transmitting module of said polishing pad and said signal receiving module of said polishing apparatus.

18. The polishing apparatus of claim 17, wherein said second signal transmitting module comprises a print circuit board, a conductive line or a connector.

19. The polishing apparatus of claim 17, wherein said second signal transmitting module is set on a surface of said polishing pad attached to said first platform.

20. The polishing apparatus of claim 10, wherein said signal receiving module comprises a wireless signal receiver.