Workpiece thickness measuring device, workpiece thickness measuring method, and workpiece polishing system

Abstract

To provide a measuring device for a thickness of a work-piece, a measuring method for the thickness of the work-piece, and a polishing system for the work-piece, capable of accurately measuring the thickness of the work-piece when a spectral interference sensor is used.SOLUTION: A measuring device for a thickness of a work-piece of the present invention, includes a housing, a measuring unit that is arranged in the housing and measures the length of the work-piece, and a rectification device that is arranged within the housing and rectifies an air flow within the housing. The measuring unit includes a spectral interference sensor. In a polishing system for the work-piece of the present invention, the measuring device for the thickness of the work-piece is installed in each of a work-piece carry-in unit and a work-piece carry-out unit. A measuring method for the length of the work-piece of the present invention is a method for measuring the length of the work-piece by using the measuring unit including the spectral interference sensor. The measuring unit is arranged in the housing, and measures the length of the work-piece by using the rectification device arranged in the housing to rectify an air flow in the housing.SELECTED DRAWING: Figure 4C

Description

[Technical Field]

[0001] The present invention relates to a workpiece thickness measuring device, a workpiece thickness measuring method, and a workpiece polishing system. [Background technology]

[0002] There are two main methods for measuring the thickness of workpieces such as semiconductor wafers. One is to measure by installing displacement sensors on the front and back sides of the workpiece, as shown in Figure 1. With this method, the thickness of the workpiece can be calculated by subtracting the distance to the front and back sides of the workpiece from the distance between the two displacement sensors.

[0003] However, with this method, it is difficult to perform measurements on the order of nanometers with a simple design due to factors such as axial misalignment between the two displacement sensors, vibrations in the measurement drive unit, and thermal expansion around the measuring instrument.

[0004] The other is a measurement method using a spectral interference sensor, as shown in Figure 2 (see, for example, Patent Document 1). With this method, the thickness can be calculated by measuring the reflected light from the front and back surfaces of the workpiece using a coaxially irradiated laser. This eliminates the axial misalignment and displacement deviation caused by vibration that occurs with the displacement meter mentioned above. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-294155 Summary of the Invention

[0006] However, because the spectral interference sensor is a transmission sensor, the measurement results are affected by the refractive index, which is a physical property of the workpiece. Temperature in particular has an effect on the refractive index. If the temperature changes while the workpiece is being measured, an error will occur in the measured thickness. As shown in Figure 3, there is a positive correlation between the workpiece temperature and the measured workpiece thickness, and as the workpiece temperature increases, the measured thickness of the workpiece will be thicker.

[0007] In response to these problems, the present invention aims to provide a workpiece thickness measuring device, a workpiece thickness measuring method, and a workpiece polishing system that can measure the thickness of a workpiece with high accuracy when using a spectral interference sensor. [Means for solving the problem]

[0008] The gist and configuration of the present invention are as follows. (1) a housing; a measuring unit disposed in the housing and configured to measure the thickness of the workpiece; a rectifying device disposed within the housing and rectifying an airflow within the housing, A workpiece thickness measuring device, characterized in that the measuring unit is equipped with a spectral interference sensor.

[0009] (2) The work thickness measuring device according to (1) above, further comprising a storage section for storing equipment.

[0010] (3) The rectifier, the measuring unit, and the storage unit are arranged in this order from the top inside the housing, a first partition portion between the rectifier and the measuring portion; A second partition is provided between the measurement unit and the storage unit, a first opening is provided in the first partition; The workpiece thickness measuring device according to (1) or (2) above, wherein the second partition portion is provided with a second opening portion.

[0011] (4) The work thickness measuring device according to (3) above, wherein the second partition portion having the second opening is a punching plate.

[0012] (5) A work thickness measuring device according to (2) or (3) above, wherein an exhaust slit is provided on the side of the housing that defines the storage section.

[0013] (6) The work thickness measuring device according to any one of (1) to (5) above, wherein the bottom of the housing is made of a punching plate.

[0014] (7) The workpiece thickness measuring device according to any one of (1) to (6) above, wherein a temperature sensor is disposed at least inside the housing.

[0015] (8) The workpiece thickness measuring device according to any one of (1) to (7) above, wherein the workpiece is a semiconductor wafer.

[0016] (9) A workpiece polishing system comprising a workpiece loading unit and a workpiece unloading unit, characterized in that a workpiece thickness measuring device described in any one of (1) to (8) above is installed in each of the workpiece loading unit and the workpiece unloading unit.

[0017] (10) The workpiece polishing system according to (9) above, further comprising a polishing unit, a cleaning unit, and a drying unit.

[0018] (11) A workpiece polishing system according to (9) or (10) above, wherein the workpiece is a semiconductor wafer.

[0019] (12) A method for measuring the thickness of a workpiece, in which the thickness of the workpiece is measured using a measuring unit equipped with a spectral interference sensor, The measurement unit is disposed in a housing, A method for measuring the thickness of a workpiece, characterized in that the thickness of the workpiece is measured by the measurement unit while rectifying the air flow within the housing using a rectifying device arranged within the housing.

[0020] (13) a step of monitoring the temperature at least inside the housing by a temperature sensor disposed at least inside the housing, and estimating an appropriate work thickness measurement time based on the monitored temperature measurement result; The method for measuring the thickness of a workpiece according to (12) above, further comprising the step of measuring the thickness of the workpiece within the estimated measurement time.

[0021] (14) A method for measuring the thickness of a workpiece described in (12) above, comprising a step of monitoring the temperature at least inside the housing using a temperature sensor arranged at least inside the housing, and determining whether the measurement accuracy is acceptable based on the monitored temperature measurement results.

[0022] (15) The method for measuring the thickness of a workpiece according to (12) or (13) above, wherein the workpiece is a semiconductor wafer. [Effects of the Invention]

[0023] According to the present invention, it is possible to provide a workpiece thickness measuring device, a workpiece thickness measuring method, and a workpiece polishing system that can measure the thickness of a workpiece with high accuracy when using a spectral interference sensor. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 10 is a schematic diagram illustrating a case where the thickness of a workpiece is measured by clamping it with a displacement sensor. [Figure 2] FIG. 1 is a schematic diagram illustrating a case where the thickness of a workpiece is measured using a spectral interference sensor. [Figure 3] FIG. 10 is a diagram showing the relationship between the temperature of the workpiece and the measured thickness of the workpiece. [Figure 4A] 1 is a schematic perspective view of a workpiece thickness measuring device according to an embodiment of the present invention; [Figure 4B] FIG. 4B is a diagram for explaining the airflow inside the housing of the device of FIG. 4A. [Figure 4C] FIG. 4B is a transparent perspective view seen through FIG. 4A. [Figure 5] FIG. 10 is a schematic perspective view of a modified example of a workpiece thickness measuring device. [Figure 6] FIG. 10 is a diagram showing the relationship between the measurement time of the workpiece thickness and the variation (6σ) of the environmental temperature. [Figure 7] 1A and 1B are top and bottom views of a workpiece polishing system according to an embodiment of the present invention; [Figure 8] FIG. 10 is a diagram showing the change over time in temperature inside and outside the housing in the example of the invention. [Figure 9] FIG. 9 is a diagram showing the difference in temperature from 10 seconds before in FIG. 8. [Figure 10] FIG. 10 is a diagram showing the temperature change inside the housing when the workpiece thickness is measured for 10 seconds, 30 seconds, 60 seconds, and 120 seconds. [Figure 11] FIG. 10 is a diagram showing the relationship between the GBIR value results of the invention examples and the GBIR value results obtained by a flatness measuring instrument (WaferSight). [Figure 12] FIG. 10 is a diagram showing the relationship between the GBIR value results of the comparative example and the GBIR value results measured by a flatness measuring instrument (WaferSight). DETAILED DESCRIPTION OF THE INVENTION

[0025] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0026] <Work thickness measuring device> Fig. 4A is a schematic perspective view of a workpiece thickness measuring device according to one embodiment of the present invention, Fig. 4B is a diagram for explaining an air flow within the housing of the device of Fig. 4A, and Fig. 4C is a transparent perspective view seen through Fig. 4A.

[0027] 4A to 4C, the workpiece thickness measuring device 1 of this embodiment includes a housing 2, a measuring unit 3 that is disposed within the housing 2 and measures the thickness of the workpiece, and a rectifying device 4 that is disposed within the housing 2 and rectifies the airflow within the housing 2. Furthermore, in the illustrated example, this device 1 includes a storage unit 5 for storing equipment 8.

[0028] In the illustrated example, the rectifier 4, the measuring unit 3, and the storage unit 5 are arranged in this order from the top inside the housing 2. A first partition (not shown) is provided between the rectifier 4 and the measuring unit 3, and a second partition 6 is provided between the measuring unit 3 and the storage unit 5.

[0029] The housing 2 is box-shaped and large enough to accommodate the rectifier 4, the measuring unit 3, and the equipment 8. In this example, the housing 2 is preferably made of a material that changes little in temperature, and can be made of a material such as a stainless steel plate with heat insulating material attached. The part of the housing 2 that defines the measuring unit 3 is provided with an inlet 2a through which the workpiece (in this example, a semiconductor silicon wafer) whose thickness is to be measured can be carried in. In addition, a plurality of exhaust slits 2b are provided on the side of the housing 2 that defines the storage unit 5. In particular, the bottom of the housing 2 is made of a punched plate 7. As described above, the housing 2 is divided into three sections, the rectifier 4, the measuring section 3, and the storage section 5, by the first partition section and the second partition section 6. In this embodiment, the first partition section has (plurality of) first openings (in this example, the first partition section is made of a punched plate), and the second partition section 6 has (plurality of) second openings (in this example, the second partition section 6 is made of a punched plate). This allows the housing 2 to have good ventilation between the rectifier 4, the measuring section 3, and the storage section 5, and furthermore, the exhaust slits 2b on the side of the storage section 5 and the punched plate 7 on the bottom allow sufficient exhaust to the outside of the housing 2.

[0030] The measurement unit 3 includes a spectral interferometric sensor 3a. The spectral interferometric sensor 3a is configured to be movable in the radial direction of the workpiece W. In this example, the measurement unit 3 further includes a holder 3b on which the workpiece W can be rotatably placed, and a drive unit (rotation motor) 3c that rotates the workpiece W by rotating the holder 3b. By placing the workpiece W on the holder 3b and rotating the holder 3b with the drive unit 3c to rotate the workpiece W while moving the spectral interferometric sensor 3a in the radial direction of the workpiece W, the thickness of the workpiece W can be efficiently measured while tracing a spiral trajectory of measurement points on the plane of the workpiece W. A known spectral interferometric sensor 3a can be used as the spectral interferometric sensor 3a.

[0031] The rectifier 4 is configured to rectify the airflow S within the housing 2. A known FFU (fan filter unit) can be used as the rectifier 4. As shown in FIG. 4B , when the airflow S is blown downward from the rectifier 4 installed above the housing 2, as described above, the housing 2 has good ventilation between the rectifier 4, the measurement unit 3, and the storage unit 5. Therefore, the airflow S passes through the rectifier 4, the measurement unit 3, and the storage unit 5, and is then exhausted to the outside of the housing 2 through the exhaust slit 2b on the side of the storage unit 5 and the holes in the punched plate 7 at the bottom. This prevents air from stagnating within the housing 2. The FFU is not particularly limited, but it is preferable to set the wind speed at 0.3 to 1.5 m / s.

[0032] Examples of equipment 8 include a power supply that supplies power to the drive unit 3c etc., a computer that records the workpiece thickness measurement results, a PLC that controls the motor etc., and measurement equipment (light source and power supply) for measuring the workpiece thickness. A vibration isolation mechanism 9 is provided at the bottom of the housing 2 (underside of the punching plate 7), allowing the workpiece thickness to be measured inside the housing 2 with reduced vibration. If a small, cylindrical vibration isolation mechanism 9 like the one shown in the figure is used, it can be easily installed in existing equipment.

[0033] Fig. 5 is a schematic perspective view of a modified workpiece thickness measuring device. As shown in Fig. 5, temperature sensors (thermocouples in this example) 10a and 10b may be disposed inside and outside the housing 2. In the illustrated example, thermocouple 10a is installed inside the part of the housing 2 that defines the measurement unit 3, and thermocouple 10b is installed outside the part of the housing 2 that defines the measurement unit 3. This makes it possible to monitor the temperatures inside and outside the housing 2 (measurement unit 3 in the illustrated example).

[0034] The following describes the effects of the workpiece thickness measuring device 1 of this embodiment. The workpiece thickness measuring device 1 of this embodiment is provided with a rectifier 4 that is disposed within the housing 2 and rectifies the airflow within the housing 2. As shown in Fig. 4B, the airflow S within the housing 2 (particularly the measurement unit 3) can be rectified, preventing air from stagnating within the housing 2 (particularly the measurement unit 3). This makes it possible to reduce temperature changes within the housing 2 (particularly the measurement unit 3) compared to temperature changes outside the housing 2, thereby reducing errors in the workpiece thickness measurement value when using a spectral interference sensor that are caused by temperature changes in the measurement environment. In this way, according to the workpiece thickness measuring device 1 of this embodiment, the thickness of the workpiece can be measured with high accuracy using a spectral interference sensor.

[0035] As in this embodiment, the workpiece thickness measurement device 1 preferably includes a storage section 5 for storing the equipment 8. In particular, the rectifier 4, the measurement section 3, and the storage section 5 are arranged in this order from top to bottom within the housing 2. A first partition is preferably provided between the rectifier 4 and the measurement section 3, and a second partition 6 is preferably provided between the measurement section 3 and the storage section 5. The first partition has a first opening, and the second partition 6 has a second opening. This allows the airflow S within the measurement section 3 to be rectified to flow from top to bottom, as shown in FIG. 4B. This further reduces temperature changes within the measurement section 3, enabling more accurate measurement of the workpiece thickness. Therefore, the second partition 6 having the second opening is preferably constructed of a punched plate. This allows for good ventilation from the measurement section 3 to the storage section 5.

[0036] Since the storage section 5 stores the equipment 8, heat is generated by the equipment 8, and it is preferable to provide exhaust slits 2b on the side of the housing 2 that defines the storage section 5, as this makes it possible to prevent heat from building up in the storage section 5 while ensuring the flow of air current S from inside the housing 2 to outside the housing 2. For the same reason, it is preferable that the bottom of the housing 2 be made up of a punched plate. When the first partition section, the second partition section 6, and the bottom of the housing 2 are constructed from a punched plate, although there are no particular limitations, it is preferable that the ratio of the sum of the hole areas to the total area of ​​the punched plate (the area when no holes are present) be 30% or more and 50% or less, and it is preferable that the holes be uniformly arranged on the punched plate. Furthermore, it is preferable that the ratio of the total hole area of ​​the exhaust slits 2b to the total area (the area when the slits are not present) of the side portions that define the storage section 5 of the housing 2 is 5% to 30%. Although there are no particular limitations as this depends on the size of the housing 2, it is preferable that the slit length is 100 to 400 mm and the slit width is 5 to 10 mm.

[0037] Furthermore, as shown in FIG. 5, the workpiece thickness measurement device 1 preferably has a temperature sensor 10a (10b) at least inside the housing 2 (both inside and outside in this example). This allows the temperature sensor 10a to monitor the temperature inside the housing 2 (measurement unit 3 in the illustrated example). FIG. 6 is a diagram showing the relationship between the workpiece thickness measurement time and the ambient temperature variation (6σ). As shown in FIG. 6, the temperature variation increases as time passes. While a longer workpiece thickness measurement time is preferable from the perspective of taking more measurement points, there is also the problem of reduced measurement accuracy due to increased temperature variation. Therefore, by setting a standard value for the allowable variation in the housing 2 (measurement unit 3 in the illustrated example) in advance, the measurement can be performed for as long as possible and the number of measurement points can be increased, thereby further improving the measurement accuracy of the workpiece thickness. In this way, it is possible to estimate an appropriate time for measuring the thickness of the workpiece based on the monitored temperature measurement results, and measure the thickness of the workpiece in the estimated measurement time. As in this example, by providing a temperature sensor 10b outside the housing 2, it is possible to determine the extent to which the internal temperature change is reduced compared to the external temperature change, and adjust the output of the rectifier 4 as appropriate.

[0038] Furthermore, the temperature at least inside (in this example, both the inside and the outside) of the housing 2 can be monitored by the temperature sensors 10a (10b) disposed at least inside (in this example, both the inside and the outside) of the housing 2, and the accuracy of the measurement can be judged based on the monitored temperature measurement results. This makes it possible to eliminate measurements with low accuracy. This pass / fail judgment can be made based only on the internal temperature change, or it can also be made taking into account the relative relationship with the external temperature change. When the relative relationship with the external temperature change is also taken into account, this can be useful in identifying the cause of large temperature changes, for example, if there is a large temperature change only inside, it can be judged to be an internal factor, and if there are large temperature changes both inside and outside, it can be judged to be an external factor.

[0039] <Workpiece polishing system> FIG. 7 is a top view and a bottom view of a workpiece polishing system 100 according to one embodiment of the present invention. In this system 100, a workpiece loading unit 101, a polishing unit 102, a cleaning unit 103, a drying unit 104, and a workpiece unloading unit 105 are arranged in this order, according to conventional practice. A front-opening unified pod (FOUP) 106 is arranged before the workpiece loading unit 101 and after the workpiece unloading unit 105. The workpiece W (in this example, a semiconductor silicon wafer) is removed from the FOUP 106. The removed workpiece W is then loaded into the workpiece loading unit 101. The workpiece W is then polished in the workpiece polishing unit 102, cleaned after polishing in the workpiece cleaning unit 103, dried after cleaning in the drying unit 104, and unloaded from the workpiece unloading unit 105. The unloaded workpiece W is then loaded back into the FOUP 106. Each unit may have a known configuration.

[0040] In this embodiment, the workpiece thickness measuring device 1 is installed in each of the workpiece carry-in unit 101 and the workpiece carry-out unit 105. The configuration of the workpiece thickness measuring device 1 is as already described in the embodiment of the workpiece thickness measuring device.

[0041] According to the workpiece polishing system 100 of this embodiment, similarly to the embodiment of the workpiece thickness measuring device, the thickness of the workpiece can be measured with high accuracy by the workpiece thickness measuring device 1. Furthermore, since the workpiece thickness measuring device 1 is installed in each of the workpiece carry-in unit 101 and the workpiece carry-out unit 105, the thickness of the workpiece before and after polishing can be measured with high accuracy, and this makes it possible to accurately calculate, for example, the amount of polishing.

[0042] <Method for measuring workpiece thickness> First, the method for measuring the thickness of a workpiece according to this embodiment can be carried out using the device 1 described in the embodiment of the device for measuring the thickness of a workpiece.

[0043] The method for measuring the thickness of a workpiece in this embodiment is a method for measuring the thickness of a workpiece W using a measuring unit 3 equipped with a spectral interference sensor, and the measuring unit 3 is arranged inside the housing 2, and measures the thickness of the workpiece W using the measuring unit 3 while rectifying the airflow inside the housing 2 using a rectifier 4 arranged inside the housing 2. As a result, as explained in the embodiment of the workpiece thickness measuring device, measurements can be performed while reducing temperature changes inside the housing 2 (particularly the measuring unit 3) compared to temperature changes outside the housing 2, and errors in the measured value of the workpiece thickness when using a spectral interference sensor, which are caused by temperature changes in the measurement environment, can be reduced. As described above, according to the method for measuring the thickness of a workpiece of this embodiment, the thickness of the workpiece can be measured with high accuracy using a spectral interference sensor.

[0044] Here, it is preferable to include a step of monitoring the temperature at least inside (in this example, inside and outside) of the housing 2 using a temperature sensor 10a (10b) arranged at least inside (in this example, inside and outside) the housing 2, estimating an appropriate measurement time for the thickness of the workpiece W based on the monitored temperature measurement results, and a step of measuring the thickness of the workpiece W in the estimated measurement time. As explained in the embodiment of the device for measuring the thickness of the workpiece W, this is because more accurate measurements can be achieved by extending the measurement time as much as possible and taking as many measurement points as possible.

[0045] It is also preferable to include a step of monitoring the temperature at least inside (in this example, inside and outside) of the housing 2 using temperature sensors 10a (10b) arranged at least inside (in this example, inside and outside) the housing 2, and judging whether the measurement accuracy is acceptable or not based on the monitored temperature measurement results. This makes it possible to eliminate measurements with low accuracy. [Example]

[0046] In order to confirm the effect of the present invention, a comparative experiment was conducted using a work thickness measuring device such as that shown in FIGS. 4A to 4C (invention example) and a general clean room (comparison example).

[0047] Figure 8 is a diagram showing the temperature changes over time inside and outside the housing 2 in the example of the invention. The rectifier 4 was turned on. As shown in Figure 8, the temperature inside the housing 2 tends to decrease over time compared to the outside, but the variation over a short period of time is small.

[0048] To clarify the above point, Figure 9 shows the temperature difference from that of Figure 8 taken 10 seconds prior. It can be seen that the temperature change inside the housing 2 over a period of about 10 seconds is small compared to the outside. From this, it can be inferred that while changes in airflow due to disturbances cause temperature changes outside, these changes are suppressed inside by rectification of the airflow.

[0049] Figure 10 shows the temperature change inside the housing when the workpiece thickness measurement time is 10 seconds, 30 seconds, 60 seconds, and 120 seconds. As shown in Figure 10, while temperature change inside the housing is suppressed, it can be seen that a shorter measurement time is more effective at suppressing temperature change. Figure 6 shows this in terms of the relationship between measurement time and temperature change variation (6σ). From this, for example, if the reference value for 6σ is set to 0.2, the measurement time can be estimated to be approximately 90 seconds.

[0050] Next, the thickness of the workpiece (a 300 mm diameter semiconductor silicon wafer) was measured using a spectral interferometric sensor for both the inventive example and the comparative example. The measurement was performed using a spiral measurement, in which the workpiece was placed on a holder and rotated by a drive unit while the spectral interferometric sensor moved radially along the workpiece, tracing a spiral trajectory to measure the workpiece's thickness. The measurement was performed at a 1 mm pitch, a rotation speed of 30 rpm, and a measurement time of 60 seconds. Separate measurements were performed using a flatness measuring instrument (WaferSight), and the results were considered to be correct. The higher the correlation with the measurement using the flatness measuring instrument (WaferSight), the higher the accuracy of the workpiece thickness measurement. The GBIR (Global Flatness Back Reference Ideal Range) value was calculated from the obtained measurements.

[0051] Fig. 11 is a graph showing the relationship between the GBIR value results of the invention examples and the GBIR value results obtained by a flatness measuring instrument (WaferSight), and Fig. 12 is a graph showing the relationship between the GBIR value results of the comparative examples and the GBIR value results obtained by a flatness measuring instrument (WaferSight). In Figs. 11 and 12, the vertical and horizontal axes are normalized. In Figs. 11 and 12, the closer the slope of the linear approximation equation is to "1," the higher the correlation between the invention examples and comparative examples and the flatness measuring instrument (WaferSight).

[0052] 11 and 12, it can be seen that the GBIR value was determined more accurately in the example of the invention than in the comparative example. This shows that the thickness of the workpiece could be measured more accurately in the example of the invention than in the comparative example. [Explanation of symbols]

[0053] 1: Workpiece thickness measuring device, 2: Housing, 2a: Loading entrance, 2b: exhaust slit, 3: Measuring part, 3a: Spectral interference sensor, 3b: Holding part, 3c: drive unit, 4: Rectifier, 5: Storage section, 6: second partition, 7: Punching plate, 8: Equipment, 9: Earthquake isolation mechanism, 10a, 10b: temperature sensors, 100: Workpiece polishing system, 101: Work loading unit, 102: Polishing unit, 103: cleaning unit, 104: Drying unit, 105: Work unloading unit, 106:FOUP, S:Airflow

Claims

1. The housing and a measuring unit disposed in the housing and configured to measure the thickness of the workpiece; a rectifying device disposed within the housing and rectifying an airflow within the housing, the measurement unit includes a spectral interference sensor, Further provided is a storage section for storing equipment, The rectifier, the measurement unit, and the storage unit are arranged in this order from the top inside the housing, a first partition portion between the rectifier and the measuring portion; a second partition section between the measurement section and the storage section; a first opening is provided in the first partition; a second opening is provided in the second partition; temperature sensors are disposed inside and outside the housing to monitor the temperatures inside and outside the housing, respectively; A workpiece thickness measuring device, characterized in that the measurement unit is configured to measure the thickness of the workpiece within a workpiece thickness measurement time estimated based on the monitored temperature measurement results.

2. The workpiece thickness measuring device according to claim 1 , wherein the second partition portion having the second opening is a punching plate.

3. 2. The workpiece thickness measuring device according to claim 1, wherein an exhaust slit is provided in a side portion of the housing that defines the storage section.

4. 2. The workpiece thickness measuring device according to claim 1, wherein the bottom of the housing is formed of a punching plate.

5. 2. The workpiece thickness measuring device according to claim 1, wherein the workpiece is a semiconductor wafer.

6. A workpiece carrying-in unit and a workpiece carrying-out unit are provided, 3. A workpiece polishing system, comprising: a workpiece thickness measuring device according to claim 1 or 2, installed in each of the workpiece carry-in unit and the workpiece carry-out unit.

7. The system for polishing a workpiece according to claim 6 , further comprising a polishing unit, a cleaning unit, and a drying unit.

8. The system for polishing a workpiece according to claim 6 , wherein the workpiece is a semiconductor wafer.

9. A method for measuring the thickness of a workpiece, comprising: measuring the thickness of the workpiece using a measuring unit equipped with a spectral interference sensor; The measurement unit is disposed in a housing, A rectifier and a storage section for storing equipment are disposed in the housing, The rectifier, the measurement unit, and the storage unit are arranged in this order from the top inside the housing, a first partition portion between the rectifier and the measuring portion; a second partition section between the measurement section and the storage section; a first opening is provided in the first partition; a second opening is provided in the second partition; The thickness of the workpiece is measured by the measuring unit while rectifying the airflow in the housing using the rectifying device, a step of monitoring the temperatures inside and outside the housing by temperature sensors disposed inside and outside the housing, respectively, and estimating a time for measuring the thickness of the workpiece based on the monitored temperature measurement results; a step of measuring the thickness of the workpiece in the estimated measurement time.

10. The method for measuring the thickness of a workpiece according to claim 9, wherein the workpiece is a semiconductor wafer.

Images