JP2005005317A - Method and apparatus for polishing semiconductor wafer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for polishing a semiconductor wafer which obtains the semiconductor wafer having a high flatness and to provide an apparatus for polishing the semiconductor wafer. <P>SOLUTION: The method for polishing the semiconductor wafer measures a temperature at different positions of a carrier plate 16 in a thickness direction by thermocouples 17A-17E. The method calculates an amount of warpage of the carrier plate 16 based on its detection signal. The method controls polishing condition, such as, for example, rotating speeds of a polishing head 13 and a polishing surface plate 12, supply amount of abrasives, etc. so that the amount of the warpage becomes a set range. Thus, the amount of the warpage of the carrier plate 16 becomes the set range. As a result, the flatness of a polishing surface of a silicon wafer W can be raised. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a semiconductor wafer polishing method and polishing apparatus, and more particularly, a semiconductor wafer in which various polishing conditions are changed and the amount of warpage of the wafer holding member is controlled to a predetermined value based on the measured temperature of the member holding the semiconductor wafer. The present invention relates to a polishing method and a polishing apparatus thereof.
[0002]
[Prior art]
After chamfering, the etched silicon wafer is subjected to mechanical and chemical polishing on the surface in the next polishing step. Here, the surface is finished to a smooth and undistorted mirror surface by the polishing apparatus.
A conventional polishing apparatus includes a polishing surface plate having a polishing cloth stretched on an upper surface thereof, and a polishing head disposed on the lower surface of the polishing surface plate so that a silicon wafer is held by a predetermined holding structure. I have.
At the time of polishing, by supplying a polishing agent (slurry) containing abrasive grains to the polishing cloth, the silicon wafer rotating integrally with the polishing head is brought into sliding contact with the surface (polishing surface) of the polishing cloth. ,Grind.
[0003]
The polishing of the silicon wafer by such a polishing apparatus is promoted by the frictional heat and reaction heat of the abrasive interposed between the polishing cloth and the silicon wafer on the sliding contact surface between the polishing cloth and the silicon wafer.
The frictional heat generates a predetermined temperature distribution on the surface of the polishing cloth and also generates a temperature distribution within the wafer surface for the silicon wafer. In addition, a predetermined temperature difference is generated for the carrier plate that holds the silicon wafer. Such a temperature difference of the wafer holding member affects the cooling effect by the abrasive supplied on the polishing cloth and the cooling effect by the cooling water supplied to the internal flow path of the polishing surface plate, and the silicon wafer from the polishing head. This is caused by a difference in work amount due to variations in polishing pressure.
The temperature difference in the wafer holding member adds warpage to the wafer holding member. That is, when the temperature of the inner portion in the radial direction of the wafer holding member is higher than that of the outer portion, the wafer holding member is warped downward. This had a great influence on the flatness of the polished surface.
[0004]
Conventionally, as a method for measuring heat generated during polishing including frictional heat and reaction heat (hereinafter referred to as polishing heat), a non-contact type infrared radiation thermometer disposed above a side of a polishing platen is used for polishing. A method for detecting the surface temperature of the polishing cloth inside is known.
[0005]
[Problems to be solved by the invention]
However, in the method of detecting the polishing heat in this way, the amount of warpage of the wafer holding member of the semiconductor wafer actually being polished could not be calculated. Therefore, it has been difficult to increase the flatness of the polished surface of the semiconductor wafer.
[0006]
OBJECT OF THE INVENTION
The object of the present invention is to measure the temperature in the thickness direction of the wafer holding member during polishing, calculate the amount of warpage based on this measured value, and further control the polishing conditions according to the amount of warpage. Another object of the present invention is to provide a method for polishing a semiconductor wafer that can increase the flatness of the polished surface of the wafer.
The present invention also provides a semiconductor wafer polishing apparatus capable of calculating the amount of warpage by measuring the temperature at a plurality of positions in the thickness direction of the wafer holding member to produce a semiconductor wafer with high flatness. That is the purpose.
[0007]
[Means for Solving the Problems]
According to the first aspect of the present invention, when the semiconductor wafer held by the wafer holding member having a predetermined thickness is brought into sliding contact with the polishing cloth to polish the semiconductor wafer, the thickness of the wafer holding member is increased. A method of polishing a semiconductor wafer that measures the temperature of different depth positions, the step of measuring the temperature of the wafer holding member during polishing by a plurality of temperature sensors that are embedded at different depth positions, and Polishing of a semiconductor wafer comprising a step of calculating a warpage amount of the wafer holding member based on the measured temperature and a step of controlling polishing conditions so that the warpage amount of the wafer holding member becomes a predetermined value. Is the method.
As a polishing apparatus for carrying out this method, for example, a method in which a semiconductor wafer is vacuum-adsorbed to a polishing head, a wax mount method in which a semiconductor wafer is wax-bonded to a polishing head via a carrier plate, or a back containing water Examples thereof include a waxless mount type apparatus that holds a semiconductor wafer on a polishing head by a pad.
Further, the polishing apparatus may be one in which the polishing head is disposed opposite to the upper surface of the polishing surface plate, or one in which the polishing head is disposed upside down.
The material of the polishing head is not limited. However, ceramics, low expansion metals (including alloys), cast iron, steel and the like are preferable.
The wafer holding member includes a polishing head or a carrier plate supported by the polishing head.
[0008]
In addition to a typical silicon wafer, for example, a gallium arsenide wafer (GaAs wafer) can be employed as the semiconductor wafer.
The polishing cloth is usually spread on the surface of the polishing platen facing the polishing head. Examples of the polishing cloth include a hard urethane pad and a non-woven pad.
Both the polishing cloth and the polishing head may be rotated, or only the polishing cloth or only the polishing head may be rotated.
As the abrasive, for example, a mixture of baked silica, colloidal silica (abrasive grains), amine (processing accelerator), organic polymer (haze inhibitor), or the like can be used. Among these, colloidal silica is provided as a transparent or opaque milky white colloidal solution in which the silicate fine particles are not aggregated and dispersed in water as primary particles.
[0009]
The temperature distribution in the polishing surface of the semiconductor wafer can be created based on temperature data obtained from each temperature sensor by arranging a plurality of temperature sensors near the wafer holding surface of the polishing head, for example. The temperature distribution is usually created by a computer. At that time, the obtained temperature distribution can be output as a table or a graph.
The polishing conditions to be controlled include, for example, the rotation speed of the polishing head, the rotation speed of the polishing surface plate, the polishing pressure from the polishing head to the semiconductor wafer, the supply amount of the abrasive, the temperature of the wafer holding member of the polishing head, and the polishing surface plate. The temperature of the refrigerant | coolant supplied to the inside refrigerant | coolant flow path etc. are mentioned. Of these, only one may be controlled, or two or more may be controlled simultaneously or with a time difference.
Control of polishing conditions based on the temperature distribution is usually automatic control using a computer. However, manual work by an operator may be used.
[0010]
As the temperature sensor, for example, a contact-type temperature sensor such as a thermocouple, a bimetal thermometer, or a thermistor thermometer can be employed. As the type of thermocouple, for example, B, R, S, etc. standardized by JIS can be adopted. Furthermore, a non-contact temperature sensor such as an optical pyrometer or a radiation thermometer such as an infrared ray can also be employed.
The temperature sensor can be embedded in the vicinity of the wafer holding surface of the head body of the polishing head. In addition, when a carrier plate is attached to the lower surface of the polishing head, it may be embedded in the carrier plate.
The number of temperature sensors used for one semiconductor wafer is two or three or more. For example, in a batch type polishing apparatus, two or more temperature sensors can be arranged for all semiconductor wafers in one batch. Alternatively, a plurality of temperature sensors may be arranged as a sample only on a specific semiconductor wafer in one batch.
The detection signal from the temperature sensor may be transmitted directly to the control unit of the polishing apparatus by using, for example, a lead wire that passes through the wiring path formed along the axis of the rotation axis of the polishing head. In addition, a data logger can be attached to the polishing head, and the digitally converted data can be transmitted using a light emitting unit (such as an infrared light emitting type) and a light receiving unit provided between the polishing head and the apparatus main body. Good.
[0011]
The invention according to claim 2 is the semiconductor wafer polishing method according to claim 1, wherein the polishing condition is a rotation speed of the wafer holding member.
[0012]
The invention according to claim 3 is the method for polishing a semiconductor wafer according to claim 1, wherein the polishing condition is a rotational speed of a polishing surface plate on which the polishing cloth is spread.
[0013]
The invention described in claim 4 is the method for polishing a semiconductor wafer according to claim 1, wherein the polishing condition is a polishing pressure acting on the semiconductor wafer via the wafer holding member.
When reducing the amount of warpage of the wafer holding member that is warped downward, the polishing pressure from the polishing head (for example, a pressure device such as an air cylinder mounted on the polishing apparatus) is reduced. On the other hand, when the warpage amount is increased, the polishing pressure is increased.
[0014]
A fifth aspect of the present invention is the semiconductor wafer polishing method according to the first aspect, wherein the polishing condition is a supply amount of a polishing agent supplied to the polishing pad.
[0015]
The invention according to claim 6 is the method for polishing a semiconductor wafer according to claim 1, wherein the polishing condition is a temperature of the wafer holding member.
The temperature of the wafer holding member is changed using, for example, a heater or a heat exchanger.
[0016]
According to a seventh aspect of the present invention, in the semiconductor wafer according to the first aspect, the polishing condition is a temperature of a refrigerant flowing in a refrigerant flow path formed inside a polishing surface plate on which the polishing cloth is spread. Polishing method.
Examples of the refrigerant include water and oil.
[0017]
According to an eighth aspect of the present invention, there is provided a polishing platen on which a polishing cloth is stretched, a wafer holding member which is disposed opposite to the polishing platen and holds a semiconductor wafer on its wafer holding surface, and this wafer holding A plurality of temperature sensors that are embedded at different depth positions in the thickness direction of the member and measure the temperature of the wafer holding member at each depth position, and the wafer based on the detection values by these temperature sensors A semiconductor wafer polishing apparatus including a calculating unit that calculates a warping amount of a holding member and a polishing condition control unit that controls polishing conditions so that the warping amount becomes a predetermined value.
[0018]
The wafer holding member means, for example, a polishing head or a carrier plate.
The temperature sensor includes, for example, a thermocouple.
The calculating means calculates the amount of warpage based on, for example, data obtained from each temperature sensor. The amount of warpage can be displayed as an image on a monitor device as a table or graph, or printed and displayed by a printer.
The polishing condition control means can include, for example, a transmission that changes the rotational speed of each rotary motor when the controlled object is the rotational speed of the polishing head and the rotational speed of the polishing surface plate.
[0019]
The invention described in claim 9 is the semiconductor wafer polishing apparatus according to claim 8, wherein the polishing condition controlled by the polishing condition control means is the rotational speed of the wafer holding member.
[0020]
The invention according to claim 10 is the semiconductor wafer polishing apparatus according to claim 8, wherein the polishing condition controlled by the polishing condition control means is the rotational speed of the polishing surface plate.
[0021]
The invention according to claim 11 is the semiconductor wafer polishing apparatus according to claim 8, wherein the polishing condition controlled by the polishing condition control means is a polishing pressure acting on the semiconductor wafer via the wafer holding member. is there.
[0022]
A twelfth aspect of the present invention is the semiconductor wafer polishing apparatus according to the eighth aspect, wherein the polishing condition controlled by the polishing condition control means is a supply amount of a polishing agent supplied to the polishing pad.
[0023]
The invention described in claim 13 is the semiconductor wafer polishing apparatus according to claim 8, wherein the polishing condition controlled by the polishing condition control means is the temperature of the wafer holding member.
[0024]
According to a fourteenth aspect of the present invention, in the semiconductor wafer according to the eighth aspect, the polishing condition controlled by the polishing condition control means is a temperature of a refrigerant flowing in a refrigerant flow path formed inside the polishing surface plate. This is a polishing apparatus.
[0025]
[Action]
According to this invention, during polishing, the temperature at different positions in the thickness direction of the wafer holding member is measured, and the amount of warpage of the wafer holding member is calculated based on the measured value.
Then, based on the obtained warpage amount, for example, the rotation speed of the polishing head, the rotation speed of the polishing platen, the polishing pressure from the polishing head, the supply amount of the abrasive, the polishing head so that the warpage amount falls within the set range. Polishing conditions such as the temperature of the (wafer holding member) and the temperature of the refrigerant supplied to the refrigerant flow path in the polishing surface plate are controlled. As a result, the warpage amount of the wafer holding member of the semiconductor wafer at the time of polishing becomes a set range. As a result, the polishing rate in the polishing surface of the semiconductor wafer becomes uniform, and the flatness of the polishing surface can be increased. The setting of the warpage amount can be determined by using the warpage amount in a batch in which a wafer with high flatness is obtained.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
A first embodiment of the present invention will be described below with reference to FIGS.
In FIG. 1, reference numeral 10 denotes a batch type polishing apparatus. The polishing apparatus 10 mainly includes a polishing surface plate 12 having a polishing cloth 11 made of a hard urethane pad spread on the surface, and an upper portion of the polishing surface plate 12. And a polishing head 13 disposed on the surface.
[0027]
The polishing surface plate 12 is driven and rotated by a rotary motor M1, and a coolant channel 12a is provided in the entire upper layer portion thereof. Cooling water (refrigerant) of a water tank (not shown) is circulated and supplied to the refrigerant flow path 12a via a supply pump P1. A slurry nozzle N is disposed above the central portion of the polishing pad 11. From the slurry nozzle N, the abrasive pumped by the slurry pump P2 flows out.
The polishing head 13 has a disk-shaped head body 14. A thick annular flange 14 a is integrally formed on the lower surface of the outer peripheral portion of the head body 14. An annular cushion 15 made of silicone rubber is fixed to the lower end surface of the annular flange 14a. A ceramic carrier plate (wafer holding member) 16 having a thickness of 20 mm is detachably supported by the head body 14 via the buffer 15.
[0028]
The carrier plate 16 has five silicon wafers W adhered to the wafer holding surface (lower surface). A portion of the wafer holding surface of the carrier plate 16 where a certain silicon wafer W is held is on one imaginary line passing through the center of the carrier plate 16 and the center of the silicon wafer W in plan view. Five small holes 16a to 16e are formed at a constant pitch. Each of the small holes 16a to 16e has a different depth and is a hole having a diameter of 1.5 to 2 mm reaching from the upper surface of the carrier plate 16 to the vicinity of the lower surface. For example, the small hole 16a is the shallowest (depth A), the small hole 16b is slightly deeper (depth B), the small hole 16c is next deeper (depth C), and the small hole 16d is deeper (depth). D), the small hole 16e is deepest (depth E).
The specific formation position of each hole 16a-16e is shown below. That is, in a plan view, a small hole 16a is formed at a position closest to the center of the carrier plate 16, a small hole 16c is formed at the wafer center position, and a small hole 16e is formed at a position farthest from the center of the carrier plate 16. The small hole 16b is formed at an intermediate position between the small hole 16a and the small hole 16c, and the small hole 16d is formed at an intermediate position between the small hole 16c and the small hole 16e.
[0029]
A total of five thermocouples (temperature sensors) 17A to 17E for measuring the temperature in the surface of the carrier plate 16 held on the wafer holding surface are inserted and fixed in the small holes 16a to 16e, respectively. Specifically, a thermocouple 17A is provided in the small hole 16a, a thermocouple 17B is provided in the small hole 16b, a thermocouple 17C is provided in the small hole 16c, a thermocouple 17D is provided in the small hole 16d, and a thermocouple 17E is provided in the small hole 16e. Has been inserted. These thermocouples 17A to 17E can detect the temperature of the carrier plate 16 at the installation position.
A data logger 18 that digitally converts detection signals from the thermocouples 17A to 17E is attached to one side portion of the upper surface of the carrier plate 16. On the head body 14, an annular weight 19 covered with a circular hood F in plan view is mounted. The entire load (static load) of the polishing head 13 by the weight 19 is applied to the carrier plate 16 through the buffer body 15.
[0030]
On the center of the head body 14, the lower end of the rotary shaft 20 extending from the rotary motor M2 built in the upper frame 10a of the polishing apparatus 10 is fixed. Further, on a part of the outer periphery of the hood F, there is a light emitting unit 22 that transmits the temperature data converted by the data logger 18 as an infrared signal toward the light receiving unit 21 provided on the lower surface of the upper frame 10a. It is fixed. The temperature data signal received by the light receiving unit 21 is sent to the control unit C.
A reflecting plate 23 whose upper surface is mirror-finished is fixed on a portion of the outer periphery of the hood F on the side opposite to the light emitting unit 22 with the rotary shaft 20 as the center. A photoelectric sensor 24 that irradiates light toward the reflection plate 23 is provided at a position on the opposite side of the lower surface of the upper gantry 10a from the light receiving unit 21 with the rotation shaft 20 as the center. The photoelectric sensor 24 measures the timing of data transmission, and an infrared signal including temperature data is emitted from the light emitting unit 22 toward the light receiving unit 21 at the transmission timing.
[0031]
Although not shown, a disk-shaped pressure plate is detachably fixed to the upper surface of the central portion of the carrier plate 16 via a pyramidal silicone rubber. Further, an air cylinder 30 (see FIG. 3) is suspended from the center of the inner surface of the head main body 14, and a pressure plate is fixed to the lower end of the rod. When the rod is protruded, the pressure plate moves downward, and the whole central portion of the carrier plate 16 is pushed downward. Accordingly, each silicon wafer W adhered to the carrier plate 16 is pressed against the polishing pad 11 of the polishing surface plate 12 with a predetermined pressure (center load).
[0032]
Here, the control circuit of the polishing apparatus according to the first embodiment will be described with reference to FIG.
A data logger 18 is connected to the input side of the control unit C. On the output side of the control unit C, the center motors of the rotary motor M1 of the polishing surface plate 12, the rotary motor M2 of the polishing head 13, the supply pump P1 of the cooling water, the slurry pump P2 for pumping the abrasive and the polishing head 13 are adjusted. Air cylinders 30 are connected to each other. The five thermocouples 17A to 17E are connected to the input side of the data logger 18.
Accordingly, detection signals for each temperature from the thermocouples 17 </ b> A to 17 </ b> E are sent to the control unit C via the data logger 18. Thereafter, in the control unit C, calculation such as a warp amount is performed by the calculation means, and a command for appropriately controlling the output toward the rotary motors M1, M2, the pumps P1, P2, and the air cylinder 30 according to the result. Is issued. Based on this command, the rotation speed of the polishing surface plate 12, the rotation speed of the polishing head 13, the temperature of the coolant, the supply amount of the abrasive, and the center load of the polishing head are appropriately controlled. A control command from the control unit C may be transmitted to only one drive source (for example, the rotary motor M1) or may be transmitted to a plurality of drive sources (including all five).
[0033]
Next, the operation of the polishing apparatus 10 according to the first embodiment will be described.
At the time of polishing, a predetermined load and relative speed are applied between the polishing cloth 11 and each silicon wafer W while supplying a polishing agent containing polishing grains such as baked silica and colloidal silica to the polishing cloth 11 on the polishing surface plate 12. Is done by giving
At the time of this polishing, the entire load of the weight 19 acts on the outer peripheral portion of the carrier plate 16 from the annular flange 14a through the buffer body 15. In addition, a central load acts on the center portion of the carrier plate 16 by the air cylinder 30. That is, the silicon wafer W is mirror-polished while maintaining a balance between the static load and the center load.
[0034]
At that time, the temperature in the plate surface of the carrier plate 16 being polished is detected as a voltage by the five thermocouples 17A to 17E. Each detection signal is digitally converted by the data logger 18 and then transmitted as an infrared signal from the light emitting unit 22 to the light receiving unit 21 at a timing measured by the photoelectric sensor 24. Next, the signal received by the light receiving unit 21 is transmitted to the control unit C, where the temperature distribution in the plate surface of the carrier plate 16 with time is obtained based on each temperature data. The obtained temperature distribution is displayed on a monitor as shown in the graph of FIG. 4 or printed by a printer.
Further, the warpage amount of the carrier plate at the time of polishing is calculated based on these temperatures.
Based on the temperature distribution and warpage amount obtained in this way, the temperature in the plate surface of the carrier plate 16 is, for example, constant (or a specific temperature distribution), and the warpage amount of the carrier plate 16 is a predetermined amount. The polishing conditions are changed so that the conditions are maintained. For example, control of the supply amount of the abrasive, control of the temperature of cooling water (not shown) flowing through the internal flow path of the polishing surface plate 12, control of the center load by the air cylinder, and the like are performed. In particular, the amount of warpage is controlled by controlling the center load. As a result, the polishing rate is made uniform within the polishing surface of the silicon wafer W, whereby the flatness of the polished silicon wafer W can be increased.
Note that the control of the warp amount or the like can also be achieved by matching the conditions when the flatness of the polished surface of the obtained polished wafer is high.
[0035]
Next, a second embodiment of the present invention will be described with reference to FIG.
This embodiment is an example in which the present invention is applied to a CMP (Chemical Mechanical Polishing) type polishing apparatus 10A. That is, although not shown, the polishing head 13A is provided with the five thermocouples 17A to 17E disclosed in the first embodiment.
As shown in FIG. 6, the polishing apparatus 10A is a waxless mount type, and an annular template 31 is fixed to the lower surface of the annular flange 14a of the head main body 14 of the polishing head 13A. A holding plate (wafer holding member) 32 serving as a holding base for the silicon wafer W is accommodated in the internal space of the head body 14. In this embodiment, small holes 16a to 16e are formed in the holding plate 32 (not shown). A back pad 33 made of nonwoven fabric having water retention is provided on the lower surface of the holding plate 32, and the temperature in the polishing surface of the silicon wafer W has a specific distribution over substantially the entire upper surface of the holding plate 32. A heater H for heating the holding plate 32 is provided. The specific distribution is, for example, a temperature distribution in a batch in which a product having a high flatness is actually obtained.
[0036]
At the time of polishing, pure water is supplied to the back pad 33, and the silicon wafer W accommodated in the hole of the template 31 is held from the back surface side by the surface tension. At this time, the entire surface of the silicon wafer W is projected downward from the end surface of the template 31 by a predetermined height. Then, the polishing surface of the silicon wafer W is rotated by rotating the polishing head 13A on the polishing surface plate 12 while supplying the abrasive containing the free abrasive grains to the polishing surface of the polishing pad 11 via the slurry nozzle N. Is mirror-polished.
Based on the temperature distribution obtained during the polishing and the amount of warpage of the holding plate 32, the temperature in the plate surface of the holding plate 32 becomes a specific distribution via the heater H by a control command from the control unit C. Controlled. Moreover, the center load is changed. Thereby, the curvature of the holding plate 32 is eliminated. Alternatively, the amount of warpage is controlled to be optimal.
As a result, the polishing rate becomes uniform in the polishing surface of the silicon wafer W, and the silicon wafer W having high flatness can be manufactured.
Other configurations, operations, and effects are in a range that can be estimated from the first embodiment, and thus description thereof is omitted.
[0037]
【The invention's effect】
According to the present invention, the temperature at a plurality of depth positions in the thickness direction of the wafer holding member of the semiconductor wafer during polishing is measured, and based on these temperatures, the warpage amount of the wafer holding member is within a set range. Since the polishing conditions are controlled, an optimum load condition can be set for polishing the semiconductor wafer, and as a result, a semiconductor wafer with high flatness can be obtained.
[Brief description of the drawings]
1 is a longitudinal sectional view of a semiconductor wafer polishing apparatus according to a first embodiment of the present invention;
FIG. 2 is a plan view of a carrier plate according to the first embodiment of the present invention.
FIG. 3 is a block diagram showing a control circuit of the semiconductor wafer polishing apparatus according to the first embodiment of the present invention;
FIG. 4 is a graph showing a temperature change with time in the polished surface of the semiconductor wafer during polishing according to the first embodiment of the present invention;
FIG. 5 is a sectional view showing a temperature sensor embedded portion of the carrier plate according to the first embodiment of the present invention.
FIG. 6 is a longitudinal sectional view of a semiconductor wafer polishing apparatus according to a second embodiment of the present invention.
[Explanation of symbols]
10, 10A polishing device,
11 Abrasive cloth,
12 Polishing surface plate,
12a refrigerant flow path,
13, 13A polishing head,
16 Carrier plate (wafer holding member),
17A-17E thermocouple (temperature sensor),
32 holding plate (wafer holding member),
C control unit,
W Silicon wafer (semiconductor wafer).

Claims (14)

When a semiconductor wafer held by a wafer holding member having a predetermined thickness is brought into sliding contact with a polishing cloth to polish the semiconductor wafer, the temperature at different depth positions in the thickness direction of the wafer holding member is measured. A method for polishing a semiconductor wafer, comprising:
Measuring the temperature of the wafer holding member during polishing with a plurality of temperature sensors embedded at different depth positions; and
Based on the measured temperature, a step of calculating the warpage amount of the wafer holding member,
And a step of controlling the polishing conditions so that the amount of warpage of the wafer holding member becomes a predetermined value. The method for polishing a semiconductor wafer according to claim 1, wherein the polishing condition is a rotation speed of the wafer holding member. The method for polishing a semiconductor wafer according to claim 1, wherein the polishing condition is a rotational speed of a polishing surface plate on which the polishing cloth is spread. The method for polishing a semiconductor wafer according to claim 1, wherein the polishing condition is a polishing pressure acting on the semiconductor wafer via the wafer holding member. The method for polishing a semiconductor wafer according to claim 1, wherein the polishing condition is a supply amount of an abrasive supplied to the polishing cloth. The method for polishing a semiconductor wafer according to claim 1, wherein the polishing condition is a temperature of the wafer holding member. The method for polishing a semiconductor wafer according to claim 1, wherein the polishing condition is a temperature of a coolant flowing in a coolant channel formed in a polishing surface plate on which the polishing cloth is spread. A polishing surface plate with a polishing cloth stretched;
A wafer holding member that is disposed opposite to the polishing surface plate and holds the semiconductor wafer on the wafer holding surface;
A plurality of temperature sensors embedded in the wafer holding member at different depth positions in the thickness direction, and measuring the temperature of the wafer holding member at each depth position;
Based on detection values by these temperature sensors, a calculation means for calculating the amount of warpage of the wafer holding member,
A polishing apparatus for a semiconductor wafer, comprising polishing condition control means for controlling polishing conditions so that the amount of warpage becomes a predetermined value. 9. The semiconductor wafer polishing apparatus according to claim 8, wherein the polishing condition controlled by the polishing condition control means is a rotation speed of the wafer holding member. 9. The semiconductor wafer polishing apparatus according to claim 8, wherein the polishing condition controlled by the polishing condition control means is a rotation speed of the polishing surface plate. 9. The semiconductor wafer polishing apparatus according to claim 8, wherein the polishing condition controlled by the polishing condition control means is a polishing pressure acting on the semiconductor wafer via the wafer holding member. 9. The semiconductor wafer polishing apparatus according to claim 8, wherein the polishing condition controlled by the polishing condition control means is a supply amount of an abrasive supplied to the polishing pad. 9. The semiconductor wafer polishing apparatus according to claim 8, wherein the polishing condition controlled by the polishing condition control means is the temperature of the wafer holding member. 9. The semiconductor wafer polishing apparatus according to claim 8, wherein the polishing condition controlled by the polishing condition control means is a temperature of a coolant flowing through a coolant channel formed inside the polishing surface plate.

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