Ion implantation apparatus

Abstract

A radiation thermometer is placed in the process chamber to accurately measure the temperature of the wafer during the implantation process.SOLUTION: The ion implantation apparatus IM, IM2 includes a processing chamber 1, a wafer transfer mechanism E that linearly reciprocates the wafer W over a first non-irradiated region R1, an irradiated region R3, and a second non-irradiated region R2 of the ion beam IB in the processing chamber 1, a housing 2 disposed in one of the first non-irradiated region R1 and the second non-irradiated region R2, a radiation thermometer 3 disposed in an atmospheric-pressure space inside the housing 2, and a window 4 that is attached to the housing 2 and transmits infrared rays emitted from the wafer W.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an ion implantation apparatus that uses a radiation thermometer to measure the wafer temperature during wafer processing. [Background technology]

[0002] During ion implantation, the wafer is supported in a predetermined position by a platen. The platen is equipped with a coolant flow path to suppress the temperature rise of the wafer. During ion implantation, the wafer temperature rises as it is irradiated with an ion beam, but if the platen has a high cooling capacity, the wafer temperature rise can be suppressed and the wafer temperature can be maintained constant.

[0003] However, depending on the beam current of the ion beam used in wafer processing and the cooling capacity of the platen, the temperature of the wafer may increase during processing. In order to monitor such a rise in wafer temperature, a technique has been proposed in Patent Document 1.

[0004] In Patent Document 1, a viewport is provided on the wall of the implantation chamber (processing chamber), and the temperature of the wafer is measured from outside the implantation chamber using a radiation thermometer. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2010-44886 Summary of the Invention [Problem to be solved by the invention]

[0006] The spot diameter of a radiation thermometer increases as the distance from the measurement target increases. If an object other than the measurement target enters the spot diameter, accurate measurement by the radiation thermometer becomes impossible. Because a wafer transport mechanism and a beam current measuring device are located in the processing chamber, there is a concern that these components may enter the spot diameter of the radiation thermometer.

[0007] For the above reasons, in order to perform accurate temperature measurement using a radiation thermometer, it is desirable to place the radiation thermometer close to the object to be measured. Radiation thermometers have low heat resistance and are easily affected by the operating environment. To perform highly accurate measurements, it is necessary to maintain a constant operating environment. For this reason, a configuration in which a radiation thermometer is placed outside the processing chamber, as in Patent Document 1, is adopted. However, the distance between the wall of the processing chamber and the wafer to be measured is long, making it difficult to perform accurate temperature measurements using a radiation thermometer.

[0008] A primary object of the present invention is to accurately measure the temperature of the wafer during implantation processing by disposing a radiation thermometer in the processing chamber. [Means for solving the problem]

[0009] The ion implanter A processing chamber; a wafer transport mechanism that linearly reciprocates a wafer within the processing chamber across a first non-irradiation region, an irradiation region, and a second non-irradiation region of the ion beam; a housing disposed in either the first non-illumination area or the second non-illumination area; a radiation thermometer disposed in a space at atmospheric pressure inside the housing; a window attached to the housing that transmits infrared light emitted from the wafer.

[0010] By providing an atmospheric pressure space inside the housing placed inside the processing chamber and placing the radiation thermometer in this space, the environment in which the radiation thermometer is used inside the processing chamber can be made constant, making it possible to place and use the radiation thermometer inside the processing chamber. Placing the radiation thermometer inside the processing chamber allows the radiation thermometer to be placed close to the wafer, thereby enabling accurate measurement of the wafer temperature during the implantation process.

[0011] To facilitate temperature measurement at specific locations on the wafer, It is desirable that the housing faces the wafer at a turning point of the reciprocating movement of the wafer.

[0012] In order to reduce costs by sharing parts, a neutralizer for neutralizing the charge on the wafer; a support frame for supporting the neutralizer, It is desirable that the support frame also serves as the housing.

[0013] In a configuration in which the neutralizer includes a permanent magnet for generating a magnetic field, the neutralizer comprises a permanent magnet; The support frame preferably includes a cooling plate having openings at locations corresponding to the windows.

[0014] To easily implement various feedback controls, It is desirable that the wafer exchange and the wafer temperature measurement by the radiation thermometer are carried out in the same non-irradiated region.

[0015] To prevent window contamination, It is desirable that a shielding member capable of opening and closing the path be provided in the path between the window and the wafer.

[0016] To prevent window contamination, It is desirable that the housing be disposed closer to the irradiation region than the position where the window is provided, and that the housing be provided with a protrusion that protrudes further than the window in the direction of travel of the ion beam within the processing chamber. [Effects of the Invention]

[0017] By providing an atmospheric pressure space inside the housing placed inside the processing chamber and placing the radiation thermometer in this space, the environment in which the radiation thermometer is used inside the processing chamber can be made constant, making it possible to place and use the radiation thermometer inside the processing chamber. Placing the radiation thermometer inside the processing chamber allows the radiation thermometer to be placed close to the wafer, thereby enabling accurate measurement of the wafer temperature during the implantation process. [Brief explanation of the drawings]

[0018] [Figure 1] Schematic plan view showing the periphery of a processing chamber of an ion implantation apparatus. [Figure 2] Temperature measurement position diagram [Figure 3] Schematic plan view of an ion implantation device equipped with a neutralizer [Figure 4] Schematic plan view of an ion implantation device equipped with a neutralizer [Figure 5] Schematic plan view of an ion implantation device equipped with a neutralizer [Figure 6] Schematic plan view of an ion implantation apparatus equipped with a shielding member. [Figure 7] Illustrative diagram of the operation of the shielding member [Figure 8] Illustrative diagram of the operation of the shielding member [Figure 9] FIG. 1 is a schematic plan view showing the periphery of a processing chamber of another ion implantation apparatus; [Figure 10] Illustration of protrusions [Figure 11] Window installation structure diagram DETAILED DESCRIPTION OF THE INVENTION

[0019] 1 is a schematic plan view showing the periphery of the processing chamber of the ion implantation apparatus IM. The Z-axis direction is the traveling direction of the ion beam IB transported into the processing chamber 1. The X-axis direction and the Y-axis direction are directions perpendicular to the Z-axis direction.

[0020] In FIG. 1, a beamline (not shown) is connected to the left side of the processing chamber 1. As the ion beam IB is transported through the beamline, it is scanned by a magnetic field or an electric field in a direction parallel to the X-axis direction. The ion beam IB scanned in a direction parallel to the X-axis direction passes through a collimator magnet arranged in the beamline. The collimator magnet deflects the ion beam IB at each position in the X-axis direction and shapes it into an ion beam IB parallel to the Z-axis direction.

[0021] In the processing chamber 1, the wafer W is supported by a platen 5. The platen 5 has an electrostatic chuck, a mechanical clamp, or both. The platen 5 may also have a cooling plate or a heater, and may have a function for adjusting the temperature of the wafer W. Furthermore, in order to improve the cooling efficiency and heating efficiency of the wafer W, a configuration in which gas is sealed between the wafer W and the platen 5 may be adopted.

[0022] A drive shaft 6 is connected to the platen 5. The drive shaft 6 is reciprocated in a direction parallel to the Y-axis direction by a drive source 7 disposed outside the processing chamber 1. As the drive shaft 6 moves, the wafer W also reciprocates in a direction parallel to the Y-axis direction. In the configuration example of FIG. 1, the wafer transport mechanism E that reciprocates the wafer W includes a drive shaft 6 and a drive source 7, but other conventionally known configurations may also be used.

[0023] During the ion implantation process, the wafer W moves through the first non-irradiation region R1, the irradiation region R3, and the second non-irradiation region R2. When the wafer W moves between the first non-irradiation region R1 and the second non-irradiation region R2, the ion beam IB is not irradiated onto the wafer W. When a part of the wafer W enters the irradiation region R3, the wafer W is irradiated with the ion beam IB, and ion implantation processing is performed on the wafer W.

[0024] The moving direction of the wafer W reverses at the ends of the first non-irradiation region R1 and the second non-irradiation region R2. The ends of each non-irradiation region R1, R2 where the moving direction of the wafer W reverses are the ends opposite the irradiation region R3. When the leading edge of the wafer W reaches this end, the wafer W moves in the opposite direction from the direction it was moving up to that point. The position where the moving direction of the wafer W reverses is called the turn-back position. In the ion implantation process, the wafer W repeatedly moves through the first non-irradiation region R1, the irradiation region R3, and the second non-irradiation region R2 until a predetermined amount of ions is implanted into the wafer W.

[0025] When exchanging the wafer W on the platen 5, the platen 5 is moved downward in the figure. Exchanging the wafer W means placing an unprocessed wafer W on the platen 5 and retrieving a processed wafer W from the platen 5. After the platen 5 moves downward, the position of the platen 5 is changed to horizontal by a tilt mechanism (not shown). When the position of the platen 5 is horizontal, the support surface for the wafer W, which is the upper surface of the platen 5, is parallel to the ZX plane.

[0026] A load lock chamber (not shown) is connected to the right side of the processing chamber 1 via a valve V. When the platen 5 is positioned horizontally, the valve V of the processing chamber 1 is opened, and the wafer W is transferred between the processing chamber 1 and the load lock chamber. To transfer the wafer W, for example, a vacuum robot (not shown) disposed in the processing chamber 1 is used.

[0027] The processing chamber 1 is provided with a housing 2 having an internal space A. The internal space A is a sealed space, and its pressure is equivalent to atmospheric pressure. A radiation thermometer 3 is disposed in the internal space A of the housing 2. A window 4 that transmits infrared rays is attached indirectly or directly to a wall surface of the housing 2. The window 4 is made of a material such as germanium or barium fluoride, for example.

[0028] In Figure 1, the wafer W is located at the turning point of the second non-irradiation region R2. The radiation thermometer 3 and the wafer W face each other in the Z-axis direction. The radiation thermometer 3 detects infrared rays emitted from the wafer W and measures the temperature of the wafer W during the implantation process. The measured temperature data S1 is transmitted to a control device C. The control device C includes a memory for storing the data and a processing circuit for calculating the data. The processing circuit may include a processor, a central processing unit, a microprocessor, a microcontroller, and / or hardware control logic.

[0029] The control device C receives the temperature data S1 and outputs a signal S2 for carrying out feedback control of each part. A specific example of feedback control will be introduced. If the temperature of the wafer W is higher than the reference temperature, the implantation process is temporarily stopped. At this time, the platen 5 stops moving and remains in the second non-irradiation region R2. The ion beam IB continues to be irradiated. Thereafter, the temperature of the wafer W is continuously measured, and when the temperature drops below the reference temperature, the transport of the wafer W is resumed. The reference temperature is stored in advance in the memory of the control device C. The control device C performs such feedback control and comparison of the measured temperature with the reference temperature. In the above-described feedback control, when the implantation process is temporarily stopped, instead of maintaining the irradiation of the ion beam IB, electrostatic or magnetic beam optical elements arranged in the beam line may be controlled to deflect the ion beam IB so that it is not transported into the processing chamber 1. Also, extraction of the ion beam from the ion source may be stopped. When the transport of the wafer W is to be resumed, if the transport of the ion beam IB into the processing chamber 1 has been stopped, the ion beam IB is transported into the processing chamber 1 in advance to make it ready for the implantation process.

[0030] If the platen 5 has a function for adjusting the temperature of the wafer W, the temperature adjustment function may be used to adjust the temperature of the wafer W to a reference temperature or lower. In this case, as for the transportation of the wafer W, if the time required for adjusting the temperature of the wafer W is equal to or shorter than the time required for the wafer W to move from the second non-irradiation region R2 to the irradiation region R3, the transportation of the wafer W may be continued. On the other hand, if the time required to adjust the temperature of the wafer W exceeds the time required for the wafer W to move from the second non-irradiation area R2 to the irradiation area R3, the transport of the wafer W is temporarily stopped in the second non-irradiation area R2 and the wafer W is kept waiting until its temperature drops below the reference temperature.

[0031] As described above, by providing the internal space A at atmospheric pressure inside the housing 2 and arranging the radiation thermometer 3 in this space, the environment in which the radiation thermometer is used inside the processing chamber 1 can be made constant. This allows the radiation thermometer 3 to be placed near the wafer W, thereby enabling the temperature of the wafer to be measured accurately during the implantation process.

[0032] A wafer transport mechanism E and a beam current measuring instrument are disposed inside the processing chamber 1. The range of the spot diameter of the radiation thermometer 3 expands depending on the distance between the radiation thermometer 3 and the wafer W. Conventionally, the radiation thermometer 3 was disposed outside the processing chamber 1, so the distance between the radiation thermometer 3 and the wafer W was long, and the spot diameter of the radiation thermometer 3 was wide. In this case, when measuring the wafer temperature with the radiation thermometer 3, it was necessary to devise a layout and configuration for the wafer transport mechanism E and the beam current measuring instrument so that they were positioned outside the wide spot diameter range. Such devise significantly reduced the degree of freedom in designing these components. However, in the above embodiment, the radiation thermometer 3 can be disposed inside the processing chamber 1, so the distance between the radiation thermometer 3 and the wafer W is shorter than in the past. As a result, it is possible to prevent a significant decrease in the degree of freedom in designing other members disposed inside the processing chamber 1, such as the wafer transport mechanism E and the beam current measuring device.

[0033] It is not essential that the temperature measurement of the wafer W be performed at the turning-back position of the wafer W. For example, as shown in FIG. 2, the temperature measurement of the wafer W by the radiation thermometer 3 may be performed while the wafer W is moving through the second non-irradiation region R2. While the wafer W is moving through the second non-irradiation region R2, the moving speed of the wafer W is relatively fast. If the temperature of the wafer W is measured at this time, it is difficult to keep the location on the wafer W where the temperature is measured constant. The wafer W has a temperature distribution within its surface. If the measurement point is not fixed, there is a concern that the measured temperature will fluctuate significantly each time a measurement is made due to the influence of temperature differences depending on the location. Considering this point, it is preferable to measure the temperature of the wafer W at the turning position of the wafer W, as shown in Figure 1. At the turning position, the transport speed of the wafer W is slower, which makes it easier to measure the temperature at a specific location on the wafer surface.

[0034] In the ion implantation process, a positively charged ion beam IB is used. As the implantation time passes, the main surface of the wafer W irradiated with the ion beam IB becomes positively charged. This charging of the wafer W can cause damage to the semiconductor devices fabricated on the wafer W. To prevent damage to the semiconductor devices due to this charging, a neutralizer is installed in the process chamber 1 to neutralize the charge on the charged wafer W.

[0035] 3 illustrates an ion implanter IM equipped with a neutralizer N. In general, in ion implanters, a high-frequency plasma flood gun or an electron source is used as the neutralizer N. The neutralizer N depicted in Figure 3 is assumed to be a high-frequency plasma flood gun. This neutralizer N generates plasma P from a noble gas, such as argon or xenon, by high-frequency discharge, and supplies low-energy electrons contained in the plasma P to the wafer W. This supply of electrons neutralizes the charged wafer W. When supplying plasma P to the wafer W, a magnetic field directed toward the wafer W may be generated by a permanent magnet M, thereby improving the efficiency of supplying plasma P to the wafer W.

[0036] The neutralizer N is supported on the wall surface of the processing chamber 1 by a support frame 8. The support frame 8 also serves as the housing 2 described in FIGS. 1 and 2. The portion of the neutralizer N that emits plasma P is exposed inside the processing chamber 1. Electrical wiring is connected to a portion on the internal space A side that is located in the Y-axis direction from the emission portion of the plasma P. The electrical wiring is arranged in the internal space A of the support frame 8 and is connected to the outside of the processing chamber 1 via a feedthrough. 1 and 2, the internal space A in which the electrical wiring is arranged is a sealed space, and its pressure is the same as atmospheric pressure. As shown in Fig. 3, by using the support frame 8 of the neutralizer N arranged in the processing chamber 1 as the housing 2, it is possible to reduce the cost of materials.

[0037] In some cases, the wafer W is heated to a high temperature of 100° C. to 500° C. and then subjected to ion implantation processing. This type of ion implantation processing is called high-temperature implantation. 3 includes a permanent magnet M, there is a concern that the permanent magnet M may be demagnetized due to the heat of the wafer W. To avoid such a risk of demagnetization, the neutralizer N may be configured to include a cooling means.

[0038] In the configuration shown in Fig. 4, a cooling plate 11 is attached to the end face of the support frame 8 on the wafer W side. A refrigerant flow path is formed inside the cooling plate 11. By flowing a refrigerant through the refrigerant flow path, the temperature rise of the permanent magnets M is suppressed through the support frame 8. The cooling plate 11 may be configured to cool the support frame 8 using a Peltier element, in addition to providing a refrigerant flow path.

[0039] There is a concern that the surface of the cooling plate 11 facing the wafer W may be damaged by plasma generated by residual gas in the processing chamber 1 and recoil particles generated when the wafer W is irradiated with the ion beam IB. Wear of the cooling plate 11 may cause problems such as leakage of the refrigerant and deterioration of the cooling function, etc. To eliminate such concerns, a protection plate 12 may be provided to cover the surface of the cooling plate 11 facing the wafer W.

[0040] As shown in FIG. 4, when the cooling plate 11 and the protection plate 12 cover the entire surface of the support frame 8, an opening H1 is provided so as not to interfere with the measurement by the radiation thermometer 3. The cooling plate 11 and the protection plate 12 may also be extended to the path of the ion beam IB. In this case, as shown in Fig. 5, the cooling plate 11 and the protection plate 12 are provided with an opening HB for the ion beam IB to pass through so as not to impede the transport of the ion beam IB.

[0041] The neutralizer N shown in Figures 3 to 5 is a high-frequency plasma flood gun, but an electron source that supplies electrons from a filament may also be used as the neutralizer N as long as it has a support frame 8 with an internal space A.

[0042] There is a concern that the window 4 may be contaminated by recoil particles from the wafer W, outgassing from the resist, etc. This contamination progresses as the ion implantation time passes. As the contamination of the window 4 progresses, it becomes difficult to accurately perform measurements with the radiation thermometer 3. In order to perform accurate measurements again using the radiation thermometer 3, it is necessary to open the processing chamber 1 to the atmosphere and perform maintenance such as cleaning or replacing the window 4. When performing maintenance, the ion implantation system IM is stopped. If the maintenance interval becomes shorter due to contamination of the window 4, the availability rate of the ion implantation system IM decreases.

[0043] 6 to 8 may be used to prevent contamination of the window 4. In Fig. 6, a shielding member 13 is disposed on the temperature measurement path between the window 4 and the wafer W. The temperature measurement path is a straight line connecting the radiation thermometer 3 and the wafer W in the Z-axis direction. The shielding member 13 is connected to a drive shaft 14. Fig. 7 is an XY plan view of the shielding member 13 in Fig. 6 as viewed from the wafer W side. Depending on the temperature measurement performed by the radiation thermometer 3, the shielding member 13 is moved using the drive shaft 14 to open and close the path for temperature measurement.

[0044] To open or close the temperature measurement path, for example, the drive shaft 14 is moved up or down as shown by arrow B1 in Figure 7. When measuring temperature with the radiation thermometer 3, the shielding member 13 is moved upward from the state shown in Figure 7 to open the temperature measurement path. Conversely, when not measuring temperature with the radiation thermometer 3, the shielding member 13 is moved downward from the position used when measuring temperature with the radiation thermometer 3, and the shielding member 13 is inserted into the temperature measurement path. This closes the temperature measurement path, making it possible to protect the window 4 from contamination sources. Further, as shown by the arrow B2 in FIG. 7, the drive shaft 14 may be rotated. Furthermore, as shown in FIG. 8, a drive shaft 14 may be connected to the end of the shielding member 13, and the temperature measurement path may be opened and closed by rotating the drive shaft 14 in the direction indicated by arrow D around the Y axis.

[0045] 6 to 8, the shielding member 13 is configured to open and close the temperature measurement path by moving a plate-like member, but it may have a different configuration. For example, the shielding member 13 may have a configuration similar to the aperture mechanism of a camera, and the temperature measurement path may be opened and closed by opening and closing the aperture.

[0046] The wafer transport mechanism E may be configured so that the wafer W moves on a linear guide. Figure 9 shows a wafer transport mechanism E that uses a ball screw. One end of the ball screw 15 is connected to a drive source 16 provided outside the processing chamber 1. A moving member (not shown) is connected to the end of the platen 5 in the X-axis direction. This moving member moves back and forth in the Y-axis direction by the rotation of the ball screw 15. In the processing chamber 1, two guide rails 17 are arranged, which are spaced apart in the Z-axis direction and support the end of the platen 5 in the X-axis direction.

[0047] 1 to 8, the ion beam IB shown in Fig. 9 may be scanned in the X-axis direction, or may be a ribbon beam that is not scanned in the X-axis direction. A ribbon beam is an ion beam IB whose cross section in the XY plane is substantially rectangular. In the cross section of this ion beam IB in the XY plane, the dimension in the X-axis direction is longer than the dimension in the Y-axis direction.

[0048] In the ion implantation apparatus IM2 shown in FIG. 9, the direction of gravity is the X-axis direction. When exchanging the wafer W, the platen 5 moves downward in FIG. 9. The platen 5 is then rotated around the Y-axis direction as the rotation axis, so that the wafer support surface of the platen 5 faces upward in the plane of the drawing. With the platen 5 in this position, the valve V is opened and the wafer W is transported between the platen 5 and the load lock chamber.

[0049] In the ion implantation apparatus IM2 shown in FIG. 9, an internal space A at atmospheric pressure is provided in the housing 2, and a radiation thermometer 3 is placed in this space, thereby making it possible to accurately measure the temperature of the wafer W during the implantation process, as in the embodiment described with reference to FIGS. 1 to 8.

[0050] In the ion implantation process, the ion beam IB is not necessarily irradiated perpendicularly to the main surface of the wafer W. Depending on the ion implantation process, the tilt angle of the platen 5 may be adjusted so that the ion beam IB is irradiated at an angle other than perpendicular to the main surface of the wafer W.

[0051] FIG. 10 shows the state of the platen 5 when the tilt angle is adjusted. When the wafer W is irradiated with the ion beam IB, particles recoil from the wafer W and scatter. When the tilt angle is adjusted as shown in Figure 10, the recoiled particles scatter from the wafer W that has passed through the irradiation region R3 in the direction indicated by the dashed arrow. At this time, there is a concern that the recoiled particles will adhere to the window 4, causing contamination of the window 4. In order to prevent contamination of the window 4 by such recoil particles, a protrusion 20 is provided on the housing 2 in FIG.

[0052] The protrusion 20 may be formed by the housing 2 itself, or may be formed by a member separate from the housing 2. The protrusion 20 is disposed closer to the irradiation region R3 than the position where the window 4 is provided, and protrudes further in the traveling direction of the ion beam IB than the window 4. By providing such a protrusion 20 on the housing 2, contamination of the window 4 by recoil particles can be suppressed. Note that a part of a member may be used as the protrusion 20. That is, if a part of a member is arranged closer to the irradiation region R3 than the position where the window 4 is provided, like the protrusion 20, and protrudes further in the direction of travel of the ion beam than the window 4, the effect of the protrusion 20 described here can be achieved.

[0053] A specific example of the structure for attaching the window 4 to the housing 2 is shown in the cross-sectional view of Fig. 11. The attachment position of the housing 2 relative to the processing chamber 1 in Fig. 11 is the same as that in Fig. 1. Inside the housing 2, the tip of the radiation thermometer 3 is attached to a mounting bracket 31. The mounting bracket 31 is screwed into a mounting flange 32 and fixed to the wall surface of the housing 2. When the various components are assembled, the window 4 is sandwiched between the components. The mounting flange 32 has an opening H2 for temperature measurement, and is fixed to the outer wall of the housing 2 with bolts. A resin packing may be installed between the mounting bracket 31 and the window 4 to cushion the impact when the window 4 is clamped. Furthermore, O-rings may be attached between the window 4 and the mounting flange 32 and between the mounting flange 32 and the outer wall of the housing 2 to improve the airtightness of the internal space A of the housing 2.

[0054] In the cross-sectional view shown in Figure 11, mounting flange 32 is divided into upper and lower sections with opening H2 in between. The lower section of mounting flange 32 corresponds to the configuration of protrusion 20 described above, and therefore has the same function as protrusion 20 in Figure 10. Thus, by adopting the mounting structure for window 4 shown in Figure 11, it is possible to obtain the effect of suppressing contamination of window 4 by protrusion 20 described in Figure 10. Similarly, the cooling plate 11 and the protection plate 12 described with reference to FIGS. 4 and 5 also correspond to the configuration of the protrusions 20, and therefore have the same contamination prevention effect as the protrusions 20.

[0055] In the embodiments described above, a single radiation thermometer 3 is used, but when measuring the temperature at multiple points on the wafer surface, multiple radiation thermometers 3 may be arranged along the Y-axis direction, the X-axis direction, or both directions to measure the temperature of the wafer W. One of the multiple radiation thermometers 3 may also be used as a verification radiation thermometer. As contamination of the window 4 progresses over time, the measurement accuracy of the radiation thermometer decreases. If the contamination is severe, it may become impossible to measure. Also, even if it is not impossible to measure, there may be an error in the actual measurement value.

[0056] The verification radiation thermometer is used only when verifying whether the values ​​of the other radiation thermometers are normal. Outside of verification, the window 4 corresponding to the verification radiation thermometer is protected by a shielding member 13 or the like. The measurement results of the actual measurement radiation thermometer and the verification radiation thermometer are compared, and if the temperature difference is outside the specified range, maintenance such as cleaning or replacing the actual measurement radiation thermometer is performed.

[0057] In the embodiments described above, the wafer W is exchanged in the first non-irradiation region R1, and the temperature of the wafer W is measured in the second non-irradiation region R2 by the radiation thermometer 3. However, both may be performed in the same non-irradiation region. When performing the following process as feedback control, if the wafer W is replaced and the temperature of the wafer W is measured in the same non-irradiated area, it is advantageous in that the time required for the process can be shortened. Specific examples of feedback control include a process in which the wafer W is immediately recovered into a cassette when the measured wafer temperature exceeds a reference temperature, or a process in which a cooling means is placed outside the processing chamber 1 and the wafer W is immediately transported to the external cooling means when the measured wafer temperature exceeds a reference temperature.

[0058] Furthermore, the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications are possible without departing from the spirit of the present invention. [Explanation of symbols]

[0059] 1 Processing chamber 2. Case 3 Radiation thermometer 4. Windows 8 Support Frame 11 Cooling plate 13 Shielding material 20 Protrusion W wafer IB ion beam R1 1st non-irradiation area R2 2nd non-irradiation area R3 irradiation area H1, H2 opening E Wafer transport mechanism N Neutralizer IM, IM2 ion implanter

Claims

1. A processing chamber; a wafer transport mechanism that linearly reciprocates a wafer within the processing chamber across a first non-irradiation region, an irradiation region, and a second non-irradiation region of the ion beam; a housing disposed in either the first non-illumination area or the second non-illumination area; a radiation thermometer disposed in a space at atmospheric pressure inside the housing; a window attached to the housing that transmits infrared light emitted from the wafer.

2. 2. The ion implantation apparatus according to claim 1, wherein the housing faces the wafer at a turning point of the reciprocating movement of the wafer.

3. a neutralizer for neutralizing the charge on the wafer; a support frame for supporting the neutralizer, The ion implanter according to claim 1 , wherein the support frame also serves as the housing.

4. the neutralizer comprises a permanent magnet; 4. The ion implanter of claim 3, wherein said support frame includes a cooling plate having an opening at a location corresponding to said window.

5. 2. The ion implantation apparatus according to claim 1, wherein the wafer exchange and the wafer temperature measurement by the radiation thermometer are performed in the same non-irradiated region.

6. 2. The ion implantation apparatus according to claim 1, further comprising a shielding member in a path between said window and said wafer, said shielding member being capable of opening and closing said path.

7. 2. The ion implantation apparatus according to claim 1, wherein the housing is disposed closer to the irradiation region than the position where the window is provided, and includes a protrusion that protrudes further than the window in the direction of travel of the ion beam within the processing chamber.

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