U.S. patent application number 13/387941 was filed with the patent office on 2012-12-13 for device and method for measuring physical parameters of slurry and chemical mechanical polishing apparatus comprising the device.
Invention is credited to Yongyong He, Xinchun Lu, Jianbin Luo, Dewen Zhao.
Application Number | 20120315826 13/387941 |
Document ID | / |
Family ID | 44778031 |
Filed Date | 2012-12-13 |
United States Patent
Application |
20120315826 |
Kind Code |
A1 |
Lu; Xinchun ; et
al. |
December 13, 2012 |
Device and Method for Measuring Physical Parameters of Slurry and
Chemical Mechanical Polishing Apparatus Comprising the Device
Abstract
The present disclosure discloses a device for measuring physical
parameters of a slurry used in a chemical mechanical polishing
apparatus and measuring method using the same. The chemical
mechanical polishing apparatus comprises a polishing head, a rotary
table, a polishing platen and a polishing pad having a
through-hole. The device for measuring physical parameters of
slurry comprises: a sensor disposed in the polishing platen and
adapted to contacted the slurry via the through-hole of the
polishing pad for measuring the physical parameters of the slurry;
a converter disposed in the rotary table and coupled to the sensor
for converting a measuring signal of the sensor into a standard
electrical signal; and a processing unit coupled to the converter
for acquiring the standard electrical signal to calculate physical
parameters of the slurry. According to the device for measuring the
physical parameters of the slurry of an embodiment of the present
disclosure, the physical parameters of slurry between the polishing
head and the polishing pad may be in-suit measured and obtained.
The present disclosure further discloses a chemical mechanical
polishing apparatus having the device for measuring the physical
parameters of the slurry.
Inventors: |
Lu; Xinchun; (Bejing,
CN) ; Zhao; Dewen; (Beijing, CN) ; He;
Yongyong; (Beijing, CN) ; Luo; Jianbin;
(Beijing, CN) |
Family ID: |
44778031 |
Appl. No.: |
13/387941 |
Filed: |
June 7, 2011 |
PCT Filed: |
June 7, 2011 |
PCT NO: |
PCT/CN11/75422 |
371 Date: |
January 30, 2012 |
Current U.S.
Class: |
451/36 ; 451/259;
451/442 |
Current CPC
Class: |
B24B 37/044
20130101 |
Class at
Publication: |
451/36 ; 451/442;
451/259 |
International
Class: |
B24B 49/10 20060101
B24B049/10; B24B 49/16 20060101 B24B049/16; B24B 49/14 20060101
B24B049/14; B24B 7/00 20060101 B24B007/00; B24B 1/00 20060101
B24B001/00 |
Claims
1. A device for measuring physical parameters of a slurry used in a
chemical mechanical polishing apparatus, the chemical mechanical
polishing apparatus comprising a polishing head, a rotary table, a
polishing platen disposed on an upper surface of the rotary table,
and a polishing pad disposed on an upper surface of the polishing
platen and opposed to the polishing head and having a through-hole,
the device comprising: a sensor disposed in the polishing platen
and adapted to contact the slurry via the through-hole of the
polishing pad for measuring the physical parameters of the slurry;
a converter disposed in the rotary table and coupled to the sensor
for converting a measuring signal from the sensor into a standard
electrical signal; and a processing unit coupled to the converter
for acquiring the standard electrical signal to obtain the physical
parameters of the slurry.
2. The device according to claim 1, wherein a first groove is
formed in the upper surface of the rotary table and covered by the
polishing platen to define a first chamber in which the converter
is disposed.
3. The device according to claim 1, wherein a second groove is
formed in the upper surface of the polishing platen and covered by
the polishing pad to define a second chamber, and the sensor is
disposed in the second chamber and corresponds to the
through-hole.
4. The device according to claim 3, further comprising a mounting
panel disposed in the second chamber, and the sensor is mounted on
the mounting panel.
5. The device according to claim 4, wherein a plurality of
through-holes are formed and arranged along a radial direction of
the polishing platen at intervals, and a plurality of sensors are
provided and arranged along the radial direction of the polishing
platen at intervals and correspond to the plurality of
through-holes respectively.
6. The device according to claim 5, wherein the plurality of
through-holes are arranged along the radial direction of the
polishing platen at equal intervals, and the plurality of sensors
are arranged along the radial direction of the polishing platen at
equal intervals.
7. The device according to claim 5, wherein the plurality of
through-holes are arranged along a plurality of radial directions
of the polishing disk, and the plurality of sensors are arranged in
a plurality of one-dimensional linear arrays along the plurality of
radial directions of the polishing disk.
8. The device according to claim 7, wherein a plurality of mounting
panels are provided and the plurality of one-dimensional linear
arrays of the sensors are correspondingly mounted on the plurality
of mounting panels.
9. The device according to claim 1, wherein the sensor is a
temperature sensor and/or a pressure sensor, and the converter is a
temperature converter and/or a pressure converter, in which the
temperature sensor is coupled to the temperature converter, and the
pressure sensor is coupled to the pressure converter.
10. The device according to claim 1, wherein the processing unit
comprises: a slip ring having a rotating part mounted on the rotary
table and coupled to the converter, in which a rotating central
axis of the rotating part of the slip ring coincides with a
rotating central axis of the rotary table; an acquisition card
coupled to a static part of the slip ring for acquiring the
standard electrical signal; a signal converter coupled to the
acquisition card for converting the standard electrical signal into
a digital signal; a calculation module coupled to the signal
converter for calculating the physical parameters of the slurry
using the digital signal; and a display terminal coupled to the
calculation module for displaying the physical parameters of the
slurry.
11. A chemical mechanical polishing apparatus, comprising: a rotary
table; a polishing platen disposed on an upper surface of the
rotary table; a polishing pad disposed on an upper surface of the
polishing platen and having a through-hole; a polishing head
opposed to the polishing pad; and a device for measuring physical
parameters of a slurry, the device comprising: a sensor disposed in
the polishing platen and adapted to contact the slurry via the
through-hole of the polishing pad for measuring the physical
parameters of the slurry; a converter disposed in the rotary table
and coupled to the sensor for converting a measuring signal from
the sensor into a standard electrical signal; and a processing unit
coupled to the converter for acquiring the standard electrical
signal to obtain the physical parameters of the slurry.
12. The chemical mechanical polishing apparatus according to claim
11, wherein a first groove is formed in the upper surface of the
rotary table and covered by the polishing platen to define a first
chamber in which the converter is disposed.
13. The chemical mechanical polishing apparatus according to claim
11, a second groove is formed in the upper surface of the polishing
platen and covered by the polishing pad to define a second chamber,
and the sensor is disposed in the second chamber and corresponds to
the through-hole.
14. A method for measuring physical parameters of a slurry,
comprising: A) during a chemical mechanical polishing process,
sector scanning a whole surface of a wafer and measuring physical
parameters of a slurry to obtain a measuring signal using the
sensor of a device for measuring physical parameters of the slurry,
the device comprising: a sensor disposed in the polishing platen
and adapted to contact the slurry via the through-hole of the
polishing pad for measuring the physical parameters of the slurry;
a converter disposed in the rotary table and coupled to the sensor
for converting a measuring signal from the sensor into a standard
electrical signal; and a processing unit coupled to the converter
for acquiring the standard electrical signal to obtain the physical
parameters of the slurry; and B) converting the measuring signal
from the sensor into a standard electrical signal using the
converter, then acquiring the standard electrical signal at a
predetermined frequency using the processing unit to obtain the
physical parameters of the slurry.
15. The method according to claim 14, wherein the sensor is a
temperature sensor and/or a pressure sensor for measuring a
temperature and/or a pressure of the slurry.
Description
FIELD
[0001] The present disclosure relates to a device for measuring
physical parameters of a slurry used in a chemical mechanical
polishing apparatus, a method for measuring the physical parameters
of the slurry using the device, and a chemical mechanical polishing
apparatus including the device for measuring the physical
parameters of the slurry.
BACKGROUND
[0002] A planarization polishing process of a film attached on a
surface of a wafer is required to perform in order to satisfy the
subsequent processing requirements during a process of fabricating
an integrated circuit. Chemical mechanical polishing (CMP) is a
widely used planarization method currently.
[0003] A basic principle of CMP is that: rotations of a polishing
head and a polishing pad may generate a relative motion required by
polishing. A wafer is carried in the polishing head and the polish
pad is attached onto a surface of a polish disk. A predetermined
pressure is applied by the polishing head to press the wafer onto a
surface of the polish pad. With the aid of the relative motion
between the wafer and the polishing pad, and with the polishing
particles in a slurry, precise polishing may be realized.
[0004] On one hand, a high material removal rate is required by CMP
to improve production efficiency, on the other hand, a high
uniformity should be ensured so as to control the non-uniformity in
a reasonable extent. Otherwise, the wafer may be scrapped. In order
to obtain a better flatness, the polishing pressure is needed to
accurately control. Many related technologies such as regional
pressure control method have been used, however the conventional
methods may only control a back-pressure of the wafer, the real
pressure between the wafer and the polishing pad is not known and
there is suitable method to measure the real pressure.
[0005] A hydrodynamic lubrication or a mixed lubrication may be
formed at the interface between the wafer and the polishing pad
because of the relative motion between the wafer and the polishing
pad. Since the back-pressure applied to the back surface of the
wafer is actually borne by a fluid pressure and a contact pressure
jointly, a distribution of the contact pressure can be calculated
from a distribution of the fluid pressure. The contact pressure is
a main factor affecting the mechanical action in the polishing
process.
[0006] A temperature distribution may have a strong influence upon
the physical performance of the polishing pad and the chemical
performance of the slurry so as to affect the CMP process.
[0007] Therefore, it is advantageous to obtain the real
distribution of the pressure and temperature between the wafer and
the polishing pad so as to control the pressure and improve the
polishing quality of the wafer.
[0008] Up to now, the distribution of the contact pressure of the
CMP interface is off line measured, the fluid pressure at the
interface is based on the study of simple test on experimental
device, which can not reflect the real pressure, and the
temperature is measured by an infrared method with low precise.
SUMMARY
[0009] The present disclosure is directed to solve at least one of
problems existing in the prior art.
[0010] Therefore, an object of the present disclosure is to provide
a device used in a chemical mechanical polishing apparatus to
in-suit measure and obtain physical parameters of a slurry between
a polishing head and a polishing pad. Another object of the present
disclosure is to provide a method for in-suit measuring the
physical parameters of the slurry using the device for measuring
the physical parameters of the slurry.
[0011] Yet another object of the present disclosure is to provide a
chemical mechanical polishing apparatus including the device for
measuring the thickness of the slurry.
[0012] In order to achieve the above objects, according to
embodiments of a first aspect of the present disclosure, a device
for measuring the physical parameters of the slurry used in the
chemical mechanical polishing apparatus is provided. The chemical
mechanical polishing apparatus comprises a polishing head, a rotary
table, a polishing platen disposed on an upper surface of the
rotary table, and a polishing pad disposed on an upper surface of
the polishing platen and opposed to the polishing head and having a
through-hole. The device for measuring the physical parameters of
the slurry according to embodiments of the present disclosure
comprises: a sensor disposed in the polishing platen and adapted to
contact the slurry via the through-hole of the polishing pad for
measuring the physical parameters of the slurry; a converter
disposed in the rotary table and coupled to the sensor for
converting a measuring signal from the sensor into a standard
electrical signal; and a processing unit coupled to the converter
for acquiring the standard electrical signal to obtain the physical
parameters of the slurry.
[0013] With the device for measuring the physical parameters of the
slurry used in the chemical mechanical polishing apparatus of the
embodiment of the present disclosure, the sensor contacts the
slurry via the through-hole in the polishing pad, and is rotated
with the polishing platen during polishing so as to sector scan a
whole surface of the wafer, so that the device may in-suit measure
the physical parameters of the slurry between the polishing head
and the polishing pad (i.e., the physical parameters of slurry
between the wafer and the polishing pad). The device also has the
converter coupled to the sensor for converting the measuring signal
of the sensor into the standard electrical signal, and the
processing unit coupled to the converter for in-suit acquiring the
physical parameters of the slurry.
[0014] In some embodiments, a first groove is formed in the upper
surface of the rotary table and covered by the polishing platen to
define a first chamber in which the converter is disposed.
[0015] In some embodiments, a second groove is formed in the upper
surface of the polishing platen and covered by the polishing pad to
define a second chamber, and the sensor is disposed in the second
chamber and corresponds to the through-hole.
[0016] In some embodiments, the device for measuring physical
parameters of slurry further comprises a mounting panel disposed in
the second chamber, and the sensor is mounted on the mounting
panel. By disposing the mounting panel in the second chamber, the
sensor (especially a plurality of sensors) may be more conveniently
disposed in the second chamber.
[0017] In some embodiments, a plurality of through-holes are formed
and arranged along a radial direction of the polishing platen at
intervals, and a plurality of sensors are provided and arranged
along the radial direction of the polishing platen at intervals and
correspond to the plurality of through-holes respectively. By
disposing the plurality of sensors to simultaneously measure the
physical parameters of slurry between the wafer and the polishing
pad at different positions, a measuring data density may be
increased so that a distribution of the physical parameters of
slurry may be obtained more accurately.
[0018] In some embodiments, the plurality of through-holes are
arranged along the radial direction of the polishing platen at
equal intervals, and the plurality of sensors are arranged along
the radial direction of the polishing platen at equal
intervals.
[0019] In some embodiments, the plurality of through-holes are
arranged along a plurality of radial directions of the polishing
disk, and the plurality of sensors are arranged in a plurality of
one-dimensional linear arrays along the plurality of radial
directions of the polishing disk.
[0020] In some embodiments, a plurality of mounting panels are
provided and the plurality of one-dimensional linear arrays of the
sensors are correspondingly mounted on the plurality of mounting
panels.
[0021] In some embodiments, the sensor is a temperature sensor
and/or a pressure sensor, and the converter is a temperature
converter and/or a pressure converter, in which the temperature
sensor is coupled to the temperature converter, and the pressure
sensor is coupled to the pressure converter.
[0022] In some embodiments, the processing unit further comprises a
slip ring having a rotating part mounted on the rotary table and
coupled to the converter, in which a rotating central axis of the
rotating part of the slip ring coincides with a rotating central
axis of the rotary table; an acquisition card coupled to a static
part of the slip ring for acquiring the standard electrical signal;
a signal converter coupled to the acquisition card for converting
the standard electrical signal into a digital signal; a calculation
module coupled to the signal converter for calculating the physical
parameters of the slurry using the digital signal; and a display
terminal coupled to the calculation module for displaying the
physical parameters of the slurry.
[0023] According to embodiments of a second aspect of the present
disclosure, a chemical mechanical polishing apparatus is provided.
The chemical mechanical polishing apparatus comprises: a rotary
table; a polishing platen disposed on an upper surface of the
rotary table; a polishing pad disposed on an upper surface of the
polishing platen and having a through-hole; a polishing head
opposed to the polishing pad; and the device for measuring the
physical parameters of the slurry according to embodiments of the
first aspect of the present disclosure, in which the sensor is
disposed in the polishing platen and adapted to contact the slurry
via the through-hole in the polishing pad for measuring the
physical parameters of the slurry, the converter is disposed in the
rotary table and coupled to the sensor for converting a measuring
signal from the sensor into a standard electrical signal, and the
processing unit is coupled to the converter for acquiring the
standard electrical signal to calculate the physical parameters of
the slurry.
[0024] With the chemical mechanical polishing apparatus of an
embodiment of the present disclosure, by employing the device for
measuring physical parameters of slurry in accordance with
embodiments of the first aspect of the present disclosure, the
physical parameters of the slurry between the polishing head and
the polishing pad (i.e., the physical parameters of the slurry
between the wafer and the polishing pad) may be in-suit measured
and obtained. Therefore, the flatness of the wafer may be improved
by using the chemical mechanical polishing apparatus to chemical
mechanical polish the wafer.
[0025] In some embodiments, the first groove is formed in the upper
surface of the rotary table and covered by the polishing platen to
define the first chamber, in which the converter is disposed.
[0026] In some embodiments, the second groove is formed in the
upper surface of the polishing platen and covered by the polishing
pad to define the second chamber, and the sensor is disposed in the
second chamber and corresponds to the through-hole.
[0027] According to embodiments of a third aspect of the present
disclosure, a method for measuring the physical parameters of
slurry is provided. The method comprises the steps of: A) during a
chemical mechanical polishing process, sector scanning a whole
surface of a wafer and measuring the physical parameters of the
slurry to obtain a measuring signal using the sensor of the device
for measuring the physical parameters of the slurry according to
embodiments of the first aspect of the present disclosure; and B)
converting the measuring signal from the sensor into a standard
electrical signal using the converter, then acquiring the standard
electrical signal at a predetermined frequency using the processing
unit to obtain the physical parameters of the slurry.
[0028] With the method of an embodiment of the present disclosure,
by using the sensor of the device for measuring physical parameters
of slurry in accordance with embodiments of the first aspect of the
present disclosure to sector scan the whole surface of the wafer,
the physical parameters of the slurry between the polishing head
and the polishing pad may be in-suit measured and obtained.
[0029] In some embodiments, the sensor is a temperature sensor
and/or a pressure sensor for measuring a temperature and/or a
pressure of the slurry.
[0030] Additional aspects and advantages of embodiments of the
present disclosure will be given in part in the following
descriptions, become apparent in part from the following
descriptions, or be learned from the practice of embodiments of the
present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] These and other aspects and advantages of the present
disclosure will become apparent and more readily appreciated from
the following descriptions taken in conjunction with the drawings
in which:
[0032] FIG. 1 is a schematic structure view of a device for
measuring physical parameters of a slurry according to an
embodiment of the present disclosure;
[0033] FIG. 2 is a top view of the device for measuring the
physical parameters of the slurry according to the embodiment of
the present disclosure shown in FIG. 1;
[0034] FIG. 3 is a schematic structure view of the device for
measuring the physical parameters of the slurry according to
another embodiment of the present disclosure;
[0035] FIG. 4 is a schematic structure view of the device for
measuring the physical parameters of the slurry according to yet
another embodiment of the present disclosure;
[0036] FIG. 5 is a schematic view of measuring the physical
parameters of slurry using the device for measuring physical
parameters of slurry according to an embodiment of the present
disclosure.
[0037] Reference signs:
[0038] polishing head 10, wafer 11, rotary table 20, first chamber
21, polishing platen 30, second chamber 31, polishing pad 40,
through-hole 41, sensor 50, converter 60, processing unit 70, slip
ring 71, an acquisition card 72, display terminal 73, mounting
panel 80.
DETAILED DESCRIPTION
[0039] Embodiments of the present disclosure will be described in
detail in the following descriptions, examples of which are shown
in the accompanying drawings, in which the same or similar elements
and elements having same or similar functions are denoted by like
reference numerals throughout the descriptions. Embodiments
described herein with reference to the accompanying drawings are
explanatory and illustrative, which are used to generally
understand the present disclosure. Embodiments shall not be
construed to limit the present disclosure.
[0040] In the description, relative terms such as "longitudinal",
"lateral", "front", "rear", "right", "left", "lower", "upper",
"horizontal", "vertical", "above", "below", "up", "top", "bottom"
as well as derivative thereof (e.g., "horizontally", "downwardly",
"upwardly", etc.) should be construed to refer to the orientation
as then described or as shown in the drawings under discussion.
These relative terms are for convenience of description and do not
require that the present disclosure be constructed or operated in a
particular orientation.
[0041] In addition, terms such as "first" and "second" are used
herein for purposes of description and are not intended to indicate
or imply relative importance or significance.
[0042] In the description, terms concerning attachments, coupling
and the like, such as "coupled" and "intercoupled", refer to a
relationship wherein structures are secured or attached to one
another through mechanical or electrical connection, or directly or
indirectly through intervening structures, unless expressly
described otherwise. Specific implications of the above phraseology
and terminology may be understood by those skilled in the art
according to specific situations.
[0043] A device for measuring physical parameters of a slurry
(polishing slurry) used in the chemical mechanical polishing
apparatus according to an embodiment of the present disclosure will
be described referring to FIGS. 1-4. As shown in FIGS. 1-4, the
chemical mechanical polishing apparatus comprises a polishing head
10, a rotary table 20, a polishing platen 30 disposed on an upper
surface of the rotary table 10 and a polishing pad 40 disposed on
an upper surface of the polishing platen 30 and opposed to the
polishing head 10. The polishing pad 40 has a through-hole 41. The
device for measuring physical parameters of slurry comprises a
sensor 50, a converter 60 and a processor 70. The sensor 50 is
disposed in the polishing platen 30 and adapted to contact the
slurry via the through-hole 41 in the polishing pad 40 for
measuring the physical parameters of the slurry. The converter 60
is disposed in the rotary table 20 and coupled to the sensor 50 for
converting a measuring signal from the sensor into a standard
electrical signal. The processing unit 70 is coupled to the
converter 60 for acquiring the standard electrical signal to obtain
the physical parameters of the slurry.
[0044] With the device for the measuring physical parameters of the
slurry according to an embodiment of the present disclosure, the
sensor 50 is disposed in the polishing platen 30, contacts the
slurry via the through-hole 41 of the polishing pad 40, and is
rotated with the polishing platen 30 during polishing process so as
to sector scan the whole surface of the wafer, so that the device
for measuring the physical parameters of the slurry may in-suit
measure the physical parameters of the slurry. The device for
measuring the physical parameters of the slurry also has the
converter 60 coupled to the sensor 50 for converting the measuring
signal of the sensor 50 into the standard electrical signal, and
the processing unit 70 coupled to the converter 60 for in-suit
acquiring the physical parameters of the slurry.
[0045] In some embodiments of the present disclosure, a first
groove may be formed in the upper surface of the rotary table 20
and covered by the polishing platen 30 to define a first chamber
21, in which the converter 60 may be disposed in the first chamber
21.
[0046] As shown in FIGS. 1-4, a plurality of through-holes 41 may
be formed and arranged along a radial direction of the polishing
platen 30 at intervals, and a plurality of sensors 50 may be
provided and arranged along the radial direction of the polishing
platen 30 at intervals. The plurality of sensors 50 may be in
one-to-one correspondence with the plurality of through-holes 41,
respectively, that is, the quantity and position of the sensors 50
are corresponded to those of the through-holes 41. By disposing the
plurality of sensors 50 to simultaneously measure the physical
parameters of the slurry between the wafer 11 and the polishing pad
40 at different positions, the measuring data density may be
increased so that the distribution of the physical parameters of
the slurry may be obtained more accurately. In an embodiment, the
plurality of sensors 50 are arranged into a one-dimensional linear
array along the radial directions of the polishing platen 30.
Specifically, the plurality of through-holes 41 may be arranged
along the radial direction of the polishing platen 30 at equal
intervals, and the plurality of sensors 50 may be arranged along
the radial direction of the polishing platen 30 at equal intervals.
The plurality of sensors 50 may be corresponded to the plurality of
through-holes 41, respectively.
[0047] In some embodiments, the sensor 50 is a temperature sensor
and/or a pressure sensor, and the converter 60 is a temperature
converter and/or a pressure converter. The temperature sensor is
coupled to the temperature converter, and the pressure sensor is
coupled to the pressure converter. In an embodiment, a plurality of
temperature sensors may be provided as the sensor 50. The plurality
of temperature sensors may be arranged along the radial direction
of the polishing platen 30 to form a one-dimensional linear array.
In another embodiment, a plurality of pressure sensors may be
provided as the sensor 50. The plurality of pressure sensors may be
arranged along the radial direction of the polishing platen to form
a one-dimensional linear array. Specifically, a plurality of
temperature sensors and a plurality of pressure sensors may be
provided as the sensor 50. The plurality of temperature sensors may
be arranged along the radial direction of the polishing platen 30
to form a one-dimensional linear temperature sensor array and the
plurality of pressure sensors may be arranged along the radial
direction of the polishing platen 30 to form a one-dimensional
linear pressure sensor array for simultaneously measuring the
temperature and pressure of the slurry.
[0048] As shown in FIG. 4, the plurality of through-holes 41 may be
arranged along a plurality of radial directions of the polishing
platen 30, and the plurality of sensors 50 may be arranged along a
plurality of radial directions of the polishing platen 30 to form a
plurality of one-dimensional linear arrays. Therefore, the
measuring data density may be further increased so that the
distribution of the physical parameters of slurry may be obtained
more accurately. Each one-dimensional linear array may comprise one
sensor 50 or a plurality of sensors 50. A plurality of temperature
sensors may be arranged along a plurality of radial directions of
the polishing platen 30 to form a plurality of one-dimensional
linear temperature sensor arrays, or a plurality of pressure
sensors may be arranged along a plurality of radial directions of
the polishing platen to form a plurality of one-dimensional linear
pressure sensor arrays, or a plurality of temperature sensors may
be arranged along a plurality of radial directions of the polishing
platen to form a plurality of one-dimensional linear temperature
sensor arrays and a plurality of pressure sensors may be arranged
along a plurality of radial directions of the polishing platen to
form a plurality of one-dimensional linear pressure sensor arrays
for simultaneously measuring the temperature and pressure of the
slurry. Specifically, the plurality of one-dimensional linear
arrays may be uniformly mounted in the polishing platen 30, that
is, the plurality of one-dimensional linear arrays may be disposed
in the polishing platen 30 at equal angle intervals along the
circumferential direction of the wafer, that is, the angles of the
two adjacent one-dimensional linear arrays may be equal (e.g. 90
degree).
[0049] In some embodiments, the polishing platen 30 may have a
mounting hole in which the sensor 50 may be mounted. One mounting
hole may be disposed when there is one sensor 50. A plurality of
mounting holes may be disposed when a plurality of sensors 50 are
provided. In this case, the sensors 50 may be mounted in the
mounting holes correspondingly.
[0050] Referring to FIG. 1, in some embodiments, a second groove
may be formed in the upper surface of the polishing platen 30 and
covered by the polishing pad 40 to define the second chamber 31.
The sensor 50 may be disposed in the second chamber 31. When the
number of the sensor 50 is large, the sensors 50 may be more
conveniently disposed by forming the second groove on the upper
surface of the polishing platen 30.
[0051] In an embodiment, the device for measuring the physical
parameters of the slurry may further comprise a mounting panel 80
disposed in the second chamber 31, and the sensor 50 may be
disposed on the mounting panel 80. By disposing the mounting panel
80 in the second chamber 31, the sensor (especially a plurality of
sensors 50) may be more conveniently disposed in the second chamber
31, and the plurality of sensors 50 may be more conveniently and
accurately arranged along the radial direction of the polishing
platen 30 at intervals. Specifically, the mounting panel 80 may be
a long strip having two arc-shape ends so as to fit within an
internal wall of the second chamber 31.
[0052] In an embodiment, the plurality of one-dimensional linear
arrays are mounted on a plurality of mounting panels 80
correspondingly, that is, one one-dimensional linear array may be
mounted on one mounting panel 80.
[0053] Referring to FIG. 1, in some embodiments, the processing
unit 70 may comprise a slip ring 71, an acquisition card 72, a
signal converter, a calculation module and a display terminal 73.
The slip ring 71 may have a rotating part mounted on the rotary
table 20 and coupled to the converter 60. A rotating central axis
of the rotating part of the slip ring 71 coincides with a rotating
central axis of the rotary table. Therefore, the rotating part of
the slip ring 71 may rotate together with the rotary table 20. The
acquisition card 72 may connect to a static part of the slip ring
71 for acquiring the standard electrical signal. The signal
converter may connect to the acquisition card 72 for converting the
standard electrical signal into a digital signal. The calculation
module may connect to the signal converter for calculating the
physical parameters of slurry using the digital signal. The display
terminal 73 may connect to the calculation module for displaying
the physical parameters of slurry. Specifically, the display
terminal 73 may be a conventional display. In an embodiment, a
computer comprising the signal converter, the calculation module
and the display terminal 73 may be used to coupled to the
acquisition card 72.
[0054] The chemical mechanical polishing apparatus according to an
embodiment of the present disclosure will be described referring to
FIG. 1. As shown in FIG. 1, the chemical mechanical polishing
apparatus in accordance with an embodiment of the present
disclosure comprises the rotary table 20, the polishing platen 30,
the polishing pad 40, the polishing head 10 and the device for
measuring the physical parameters of the slurry. The polishing
platen 30 is disposed on the upper surface of the rotary table 20.
The polishing pad 40 having a through-hole is disposed on the upper
surface of the polishing platen 30. The polishing head 10 is
opposed to the polishing pad 40. The device for measuring the
physical parameters of the slurry may be the device for measuring
the physical parameters of the slurry according to the above
embodiments of the present disclosure. The sensor 50 is disposed in
the polishing platen 30 and adapted to contact the slurry via the
through-hole 41 of the polishing pad 40 for measuring the physical
parameters of the slurry. The converter 60 is disposed in the
rotary table 20 and coupled to the sensor 50 for converting the
measuring signal of the sensor into the standard electrical signal.
The processing unit 70 is coupled to the converter 60 for acquiring
the standard electrical signal to calculate the physical parameters
of the slurry.
[0055] The physical parameters of the slurry between the wafer 11
and the polishing pad 40 may be in-suit measured and obtained by
the chemical mechanical polishing apparatus having the device for
measuring the physical parameters of the slurry according to the
above embodiments of the present disclosure. Thus, the flatness of
the wafer 11 may be improved by using the chemical mechanical
polishing apparatus to chemical mechanical polish the wafer 11.
[0056] In an embodiment, the first groove may be formed in the
upper surface of the rotary table 20 and covered by the polishing
platen 30 to define the first chamber 21. The converter 60 may be
disposed in the first chamber. In another embodiment, as shown in
FIG. 1, the second groove may be formed in the upper surface of the
polishing platen 30 and covered by the polishing pad 40 to define
the second chamber 31. The sensor 50 may be disposed in the second
chamber 31. When the number of the sensor 50 is large, the sensors
50 may be more conveniently disposed by forming the second groove
on the upper surface of the polishing platen 30.
[0057] A method for measuring the physical parameters of the slurry
according to an embodiment of the present disclosure will be
described referring to FIG. 5. As shown in FIG. 5, the method
according to an embodiment of the present disclosure comprises the
following steps.
[0058] A) during a chemical mechanical polishing process, sector
scanning the whole surface of the wafer and measuring the physical
parameters of the slurry to obtain a measuring signal using the
sensor 50 of the device for measuring physical parameters of slurry
according to the above embodiments of the present disclosure;
and
[0059] B) converting the measuring signal measured from the sensor
50 into a standard electrical signal using the converter 60, then
acquiring the standard electrical signal at a predetermined
frequency using the processing unit 70 to obtain the physical
parameters of the slurry.
[0060] Specially, as shown in FIG. 5, R.sub.j is a radial position
of the sensor 50, j is a serial number of the sensor 50, and i is a
serial number of an acquisition angle position of physical
parameters measuring data. An angle position interval between two
adjacent acquisitions may be controlled by controlling the
acquisition frequency of the acquisition card 72 depending on
requirements. The sensor 50 is rotated with the polishing platen 30
so as to sector scan the whole surface of the wafer, so that
distributions of the physical parameters of slurry (such as
temperature and/or pressure) between the wafer 11 and the polishing
pad 40 are obtained. For instance, the number of the sensor 50 is
n, and the acquisition number of the physical parameters measuring
data is m. Thus, m.times.n data may be obtained when the sensor 50
is rotated by one turn with the polishing platen 30. As shown in
FIG. 5, an acquisition of distance measuring data starts at the
position of i=1, and ends at the position of i=m. The physical
parameters of slurry may be measured by the corresponding sensor,
for instance, the temperature of slurry may be measured by the
temperature sensor, or the pressure of slurry may be measured by
the pressure sensor, or the temperature and pressure may be
measured by the temperature sensor and the pressure sensor,
respectively.
[0061] With the embodiments of the present disclosure, the physical
parameters of the slurry between the polishing head 10 and the
polishing pad 40 may be in-suit measured and obtained. Therefore, a
flatness of the wafer 11 may be improved based on the measurement
data.
[0062] Reference throughout this specification to "an embodiment",
"some embodiments", "an embodiment", "an example", "a specific
examples", or "some examples" means that a particular feature,
structure, material, or characteristic described in connection with
the embodiment or example is included in at least an embodiment or
example of the present disclosure. Thus, the appearances of the
phrases such as "in some embodiments", "in an embodiment", "in an
embodiment", "an example", "a specific examples", or "some
examples" in various places throughout this specification are not
necessarily referring to the same embodiment or example of the
present disclosure. Furthermore, the particular features,
structures, materials, or characteristics may be combined in any
suitable manner in one or more embodiments or examples.
[0063] Although explanatory embodiments have been shown and
described, it would be appreciated by those skilled in the art that
changes, alternatives, and modifications all falling into the scope
of the claims and their equivalents may be made in embodiments
without departing from spirit and principles of the present
disclosure.
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