Process monitor and process monitoring method

Abstract

A light detector individually detects the intensities of a plurality of mutually different wavelength bands of radiant light from a semiconductor member during annealing. A processing device derives a physical quantity that pertains to the semiconductor member and changes due to the annealing, on the basis of the intensities of the plurality of wavelength bands detected by the light detector. The physical quantity that pertains to the semiconductor member and changes due to the annealing can be measured without damaging the semiconductor member.

Description

[Technical field]

[0001] The present invention relates to a process monitor and a process monitoring method for determining a physical quantity that changes due to annealing of a semiconductor member. [Background technology]

[0002] Conventionally, as an example of a method for grasping the in-plane distribution of the activation state of a semiconductor wafer in which a dopant is implanted and activation annealed, the measurement of sheet resistance is performed. The activation state of the dopant can be evaluated from the in-plane distribution of the sheet resistance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-81348 A Summary of the Invention [Problem to be solved by the invention]

[0004] The four-probe method is generally used to measure sheet resistance. Measurement of sheet resistance using the four-probe method is performed after annealing using a device separate from the activation annealing device. This makes the measurement of sheet resistance an offline process, which is time-consuming. In addition, the semiconductor wafer is damaged because the probe must be brought into contact with the wafer. There is also a demand to measure the temperature of the semiconductor wafer during annealing in order to determine whether the annealing results are good or bad.

[0005] An object of the present invention is to provide a process monitor and a process monitoring method capable of measuring a physical quantity related to a semiconductor component that changes due to annealing without damaging the semiconductor component. [Means for solving the problem]

[0006] According to one aspect of the present invention, a photodetector for separately detecting intensities of a plurality of mutually different wavelength ranges of radiated light from the semiconductor member during annealing; A processing device that determines a physical quantity related to the semiconductor member that changes due to annealing based on the intensities of a plurality of wavelength ranges detected by the photodetector; and Have death, The light in the wavelength range of the light for annealing from the semiconductor member is not incident on the photodetector. A process monitor is provided.

[0007] According to another aspect of the invention, Annealing the semiconductor member; The intensities of a plurality of mutually different wavelength ranges of radiated light from the semiconductor member during annealing are A photodetector configured so that light in the wavelength range of light for annealing from the semiconductor member is not incident thereon. Measured separately, A process monitoring method is provided for determining a physical quantity related to the semiconductor member that changes due to annealing based on the measurement results. Effect of the Invention

[0008] The annealing method detects the radiated light from the semiconductor material and determines the physical quantity of the semiconductor material that changes due to annealing, without damaging the semiconductor material. Furthermore, by separately measuring the intensities of the radiated light in multiple wavelength ranges, the measurement accuracy of the physical quantity can be improved. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a laser annealing apparatus equipped with a process monitor according to an embodiment. [Diagram 2] FIG. 2A is a schematic diagram showing one example of a configuration of a photodetector and optical components arranged in the path of the radiated light, and FIG. 2B is a schematic diagram showing another example of a configuration of a photodetector and optical components arranged in the path of the radiated light. [Diagram 3] FIG. 3 is a graph showing an example of the pulse of a pulsed laser beam output from a laser light source and the output signal waveforms of two light receiving parts of a photodetector. [Figure 4]4A and 4B are graphs showing an example of a temperature distribution in the depth direction when a pulse laser beam is incident on a semiconductor wafer. [Diagram 5] 5A to 5D are graphs showing temperature distribution in the depth direction when the pulse width of a pulse laser beam is constant and the pulse energy is varied. [Figure 6] FIG. 6 is a graph showing curve approximation of a scatter diagram in which an example of output values ​​of two light receiving elements is plotted against pulse energy. [Figure 7] FIG. 7 is a flow chart showing a procedure for performing laser annealing on a semiconductor wafer using a laser annealing apparatus equipped with a process monitor according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A process monitor and a process monitoring method according to an embodiment will be described with reference to FIGS.

[0011] 1 is a schematic diagram of a laser annealing apparatus equipped with a process monitor according to an embodiment. This laser annealing apparatus includes a laser optical system 10, a chamber 30, a photodetector 20, a processing device 40, a storage device 41, an output device 42, and an input device 43. The function of the process monitor is realized by the photodetector 20, the processing device 40, etc.

[0012] The laser optical system 10 includes a laser light source 11, a uniformizing optical system 12, and a folding mirror 13. The laser light source 11 outputs a laser beam in the infrared region. For example, a laser diode with an oscillation wavelength of 808 nm can be used as the laser light source 11. The uniformizing optical system 12 uniformizes the beam profile of the laser beam output from the laser light source 11. The folding mirror 13 reflects the laser beam that has passed through the uniformizing optical system 12 downward.

[0013] A window 32 that transmits a laser beam is provided on the top plate of the chamber 30, and a stage 31 is placed inside the chamber 30. A semiconductor wafer 35, which is an object to be annealed, is held on the stage 31. A dopant is implanted into the surface layer of the semiconductor wafer 35. An ion implantation method, for example, is used to implant the dopant. Before annealing, the dopant is not activated. For example, a silicon wafer can be used as the semiconductor wafer 35. For example, phosphorus (P), arsenic (As), boron (B), etc. can be used as the dopant.

[0014] The laser beam output from the laser optical system 10 passes through the dichroic mirror 25 and the window 32 and is incident on the semiconductor wafer 35 held on the stage 31. Mirrors, lenses, etc. may be arranged on the path of the laser beam as necessary. The beam spot of the laser beam on the surface of the semiconductor wafer 35 has an elongated shape that is long in one direction, for example, about 3 mm to 5 mm in length and about 0.1 mm to 0.3 mm in width. When the laser beam is incident on the semiconductor wafer 35, the surface layer of the semiconductor wafer 35 is heated at the position of the beam spot. The stage 31 is controlled by the processing device 40 to move the semiconductor wafer 35 in two directions parallel to its surface. By scanning the beam spot on the surface of the semiconductor wafer 35 in its width direction and sub-scanning it in its length direction, it is possible to laser anneal almost the entire area of ​​the upper surface of the semiconductor wafer 35.

[0015] When the laser beam is incident on the semiconductor wafer 35, the surface layer at the incident position is heated, activating the dopant. Radiant light is emitted from the heated portion. A part of the radiant light emitted from the semiconductor wafer 35 is reflected by the dichroic mirror 25 and enters the photodetector 20. The dichroic mirror 25 transmits light in a wavelength range shorter than 1 μm, for example, and reflects light in a wavelength range longer than 1 μm. Lenses, optical filters, etc. may be arranged on the path of the radiant light from the semiconductor wafer 35 to the photodetector 20 as necessary. The photodetector 20 and the optical components on the path of the radiant light will be described later with reference to FIGS. 2A and 2B.

[0016] The processing device 40 acquires the detection signal output from the photodetector 20 in synchronization with each shot of the pulsed laser beam. Furthermore, the magnitude (output value) of the acquired detection signal is stored in the storage device 41 in association with a position within the surface of the semiconductor wafer 35. As an example, for each shot of the pulsed laser beam, a time waveform of the output value is obtained corresponding to the time change in the intensity of the radiated light. The output value stored in the storage device 41 is, for example, a peak value of the time waveform for each shot of the pulsed laser beam.

[0017] Various commands and data for instructing the operation of the process monitor and the laser annealing apparatus are input to the processing device 40 through an input device 43. The processing device 40 outputs to an output device 42 the results of monitoring by the process monitor.

[0018] 2A is a schematic diagram showing an example of the configuration of the photodetector 20 and optical components arranged in the path of the radiated light. The radiated light is emitted from a region corresponding to the beam spot 37 of the pulsed laser beam incident on the surface of the semiconductor wafer 35. The emitted radiated light is incident on the photodetector 20 through two lenses 26. For example, one of the two lenses 26 is arranged between the dichroic mirror 25 (FIG. 1) and the semiconductor wafer 35, and the other is arranged between the dichroic mirror 25 and the photodetector 20. The two lenses 26 constitute an imaging optical system that images the beam spot 37 on the surface of the semiconductor wafer 35 at the position where the photodetector 20 is arranged. That is, the surface of the semiconductor wafer 35 and the light receiving surface of the photodetector 20 have a relationship of an object plane and an image plane.

[0019] The photodetector 20 includes two light receiving sections 21 that separately detect the intensity of the radiated light. The two light receiving sections 21 are arranged at different positions in the longitudinal direction of the image 38 of the beam spot 37. The two light receiving sections 21 include optical sensors 22 that have mutually different peak sensitivity wavelengths. Each of the optical sensors 22 has sensitivity in the infrared wavelength range, and outputs a signal (voltage) whose magnitude corresponds to the intensity of the incident radiated light. The signals output from the two optical sensors 22 are input to a processing device 40.

[0020] Fig. 2B is a schematic diagram showing another example of the configuration of the photodetector 20 and the optical components arranged in the path of the radiated light. In the example shown in Fig. 2A, the two light receiving sections 21 each include a light sensor 22 with a different peak sensitivity wavelength. In contrast, in the example shown in Fig. 2B, the two light receiving sections 21 each include a light sensor 22 with the same spectral sensitivity characteristics and a bandpass filter 23 with a different passing wavelength range. The radiated light transmitted through the bandpass filter 23 is incident on the light sensor 22. As a result, the peak sensitivity wavelengths of the two light receiving sections 21 are different.

[0021] 3 is a graph showing an example of the pulse of the pulsed laser beam output from the laser light source 11 and the output signal waveforms of the two light receiving sections 21 of the photodetector 20. When the laser pulse rises at time t1, the output value of the light receiving section 21 gradually rises in response to the rise in temperature of the surface layer of the semiconductor wafer 35. When the laser pulse falls at time t2, the output value of the light receiving section 21 gradually falls in response to the drop in temperature of the surface layer of the semiconductor wafer 35. The peak intensity Vp of the output of the light receiving section 21 due to the laser pulse from time t1 to t2 is stored in the storage device 41 for each light receiving section 21. Usually, this peak intensity Vp differs between the two light receiving sections 21.

[0022] Next, the excellent effects of this embodiment will be described with reference to FIGS. 4A to 5D. Figures 4A and 4B are graphs showing an example of the depth-direction temperature distribution at the time of laser pulse fall when a pulsed laser beam is incident on the semiconductor wafer 35. The horizontal axis of the graphs in Figures 4A and 4B represents the depth from the surface of the semiconductor wafer 35, and the vertical axis represents the temperature. The solid and dashed lines in Figures 4A and 4B respectively show the temperature distributions when laser pulses with the same pulse energy and relatively long and short pulse widths are incident.

[0023] When the pulse energy is the same, the peak power increases as the pulse width decreases. For this reason, the temperature TS at the outermost surface (depth zero position) when the pulse width is short is higher than the temperature TL at the outermost surface when the pulse width is long. When the pulse width increases, the amount of heat conducted in the depth direction during the period when the laser pulse is incident increases. Conversely, when the pulse width decreases, the amount of heat conducted in the depth direction during the period when the laser pulse is incident decreases. Regardless of the pulse width, the temperature decreases as the depth from the surface increases, but since the amount of heat conducted in the depth direction is smaller when the pulse width is shorter, the degree of temperature decrease is greater when the pulse width is short. For this reason, in a region deeper than a certain depth Da, the temperature when the pulse width is long is higher than the temperature when it is short.

[0024] The radiant light radiated from the outermost surface reaches the photodetector 20 without being absorbed by the semiconductor wafer 35. In contrast, a part of the radiant light radiated from a deep region is absorbed by the semiconductor wafer 35 itself before reaching the photodetector 20. The amount absorbed depends on the absorption coefficient of the semiconductor wafer 35. This absorption coefficient depends on the wavelength. Radiant light in a wavelength range with a large absorption coefficient is less likely to be radiated from a deep region of the semiconductor wafer 35 to the outside.

[0025] In the following description, to simplify the absorption phenomenon of the radiant light, it is assumed that one light-receiving part 21 detects the radiant light radiated from a region shallower than the depth D1, and the other light-receiving part 21 detects the radiant light radiated from a region shallower than the depth D2 (D2 < D1).

[0026] The detection value of one light receiving unit 21 changes in response to the area of ​​the hatched portion in a region shallower than depth D1 as shown in Fig. 4A. The detection value of the other light receiving unit 21 changes in response to the area of ​​the hatched portion in a region shallower than depth D2 as shown in Fig. 4B.

[0027] In the example shown in FIG. 4A, in the region where the depth is shallower than Da, the area of ​​the temperature distribution when the pulse width is short is larger than the area of ​​the temperature distribution when the pulse width is long, and the difference between them is A. In the region where the depth is from Da to D1, the area of ​​the temperature distribution when the pulse width is long is larger than the area of ​​the temperature distribution when the pulse width is short, and the difference between them is B. When the areas A and B are equal, the area S11 of the graph of the temperature distribution when the pulse width is long is almost equal to the area S12 of the graph of the temperature distribution when the pulse width is short. Therefore, the temperature distribution of the solid line and the temperature distribution of the broken line in FIG. 4A cannot be distinguished only by the detection value of the light receiving unit 21 that detects the radiated light from the region where the depth is shallower than D1. Therefore, it is difficult to accurately obtain the maximum temperature reached on the outermost surface of the semiconductor wafer 35.

[0028] In contrast, in the example shown in Fig. 4B, in the region from depth Da to D2, the area of ​​the temperature distribution when the pulse width is long is larger than the area of ​​the temperature distribution when the pulse width is short, and the difference is C. Area C is smaller than area A. Therefore, area S21 of the graph of the temperature distribution when the pulse width is long is smaller than area S22 of the graph of the temperature distribution when the pulse width is short. Because areas S21 and S22 are different, it is possible to distinguish between the temperature distribution indicated by the solid line and the temperature distribution indicated by the dashed line in Fig. 4B based on the detection value of light receiving unit 21 that detects radiated light from a region shallower than D2.

[0029] As in the present embodiment, by separately measuring the intensities of radiant light in different wavelength ranges using two light receiving parts 21, it becomes possible to more accurately measure the temperature of the outermost surface of the semiconductor wafer 35 when the temperature distribution in the depth direction is different.

[0030] Figs. 5A to 5D are graphs showing the temperature distribution in the depth direction when the pulse width of the pulsed laser beam is kept constant and the pulse energy is varied. The horizontal axis of the graphs in Figs. 5A to 5D represents the depth from the surface of the semiconductor wafer 35, and the vertical axis represents the temperature.

[0031] Figs. 5A and 5B show the temperature distribution when a pulsed laser beam is incident one shot under the conditions of pulse energies E1 and E2 (E1 < E2) where the temperature at the outermost surface of the semiconductor wafer 35 does not exceed the melting point. The temperature is highest at the outermost surface and decreases with increasing depth. When the pulse energy increases from E1 to E2, the temperature at each depth of the semiconductor wafer 35 increases, but the shape of the temperature distribution is almost maintained.

[0032] The peak intensity Vp (Fig. 3) of the signal output from the light receiving part 21 that detects the radiation light from the region shallower than the depth D1 becomes the size corresponding to the area S11 (Fig. 5A) when the pulse energy is E1, and becomes the size corresponding to the sum of the area S11 (Fig. 5A) and the increment ΔS11 (Fig. 5A) when the pulse energy is E2. The peak intensity Vp (Fig. 3) of the signal output from the light receiving part 21 that detects the radiation light from the region shallower than the depth D2 becomes the size corresponding to the area S21 (Fig. 5B) when the pulse energy is E1, and becomes the size corresponding to the sum of the area S21 (Fig. 5B) and the increment ΔS21 (Fig. 5B) when the pulse energy is E2.

[0033] Figs. 5C and 5D show the temperature distribution when a pulsed laser beam is incident one shot under the conditions of pulse energies E3 and E4 (E3 < E4) where the temperature at the outermost surface of the semiconductor wafer 35 is above the melting point. Under the condition of the pulse energy E3, the temperature at the outermost surface of the semiconductor wafer 35 reaches the melting point. Under the condition of the pulse energy E4, the surface layer part of the semiconductor wafer 35 melts. When the melting of the surface layer part of the semiconductor wafer 35 starts, the temperature at the outermost surface is almost fixed at the melting point. For this reason, the temperature at the outermost surface is almost the same when the pulse energy is E3 and when it is E4. Since the temperature in the deep region that has not melted increases with the increase in the pulse energy, the temperature when the pulse energy is E4 is higher than the temperature when the pulse energy is E3.

[0034] The peak intensity Vp (FIG. 3) of the signal output from the light receiving unit 21 detecting the radiated light from a region shallower than D1 is equivalent to the area S11 (FIG. 5C) at pulse energy E3, and is equivalent to the sum of the area S11 (FIG. 5C) and the increment ΔS11 (FIG. 5C) at pulse energy E4. The peak intensity Vp (FIG. 3) of the signal output from the light receiving unit 21 detecting the radiated light from a region shallower than D2 is equivalent to the area S21 (FIG. 5D) at pulse energy E3, and is equivalent to the sum of the area S21 (FIG. 5D) and the increment ΔS21 (FIG. 5D) at pulse energy E4. For simplicity, the difference between the emissivity from a semiconductor in a molten state and the emissivity from a semiconductor in a solid state is not taken into consideration.

[0035] When the outermost surface of the semiconductor wafer 35 starts to melt, the temperature of the outermost surface hardly increases even if the pulse energy is increased, so the ratio of the increment ΔS11 to the area S11 (FIG. 5C) and the ratio of the increment ΔS21 to the area S21 (FIG. 5D) become smaller than the ratios in the case where no melting occurs (FIGS. 5A, 5B). That is, the slope of the change in the output value of the light-receiving unit 21 relative to the increment in the pulse energy becomes gentler. The pulse energy when this slope starts to become gentler can be considered to be the energy condition for the start of melting. In order to anneal the semiconductor wafer 35 at as high a temperature as possible under conditions that do not melt the semiconductor wafer 35, it is desirable to accurately find this energy condition for the start of melting.

[0036] 6 is a graph showing curve approximation of a scatter diagram in which the output values ​​of the two light receiving sections 21 are plotted against the pulse energy. The detection values ​​of the light receiving section 21 detecting radiated light from regions shallower than the depths D1 and D2 are shown by the thick curve D1 and thin curve D2, respectively.

[0037] In the scatter diagram shown in Fig. 6, suppose that melting starts when the pulse energy is E1. The slope of the graph changes near the condition where melting starts, but no clear bending point appears. For this reason, it is difficult to accurately find the condition where melting starts from the measurement results of one light receiving part 21.

[0038] After the melting starts, the ratios of the increments ΔS11 (FIG. 5C) and ΔS21 (FIG. 5D) to the areas S11 (FIG. 5C) and S21 (FIG. 5D) are smaller than the ratios of the increments ΔS11 (FIG. 5A) and ΔS21 (FIG. 5B) to the areas S11 (FIG. 5A) and S21 (FIG. 5B) before the melting starts. Therefore, when the pulse energy exceeds E1, the slope of the graph becomes gentler. However, the degree to which the ratio of the increment ΔS21 to the area S21 becomes smaller is greater than the degree to which the ratio of the increment ΔS11 to the area S11 becomes smaller. This is because the temperature rise is suppressed in the region shallower than the depth D2. Therefore, in the graph shown in FIG. 6, the degree to which the slope of the graph becomes gentler at the point when the pulse energy exceeds E1 is greater for the curve D2 than for the curve D1.

[0039] Since the degree to which the slopes of the curves D1 and D2 become gentle is different, by comparing the changes in the output values ​​of the two light receiving parts 21 when the pulse energy is changed, it is possible to more accurately identify the pulse energy that satisfies the melting start condition and the output value of the light receiving part 21 at that time. For example, the pulse energy E1 at the melting start point can be more accurately identified from the relationship between the difference between the value shown by the curve D1 and the value shown by the curve D2 with respect to the pulse energy and the pulse energy.

[0040] In order to increase the accuracy of identifying the pulse energy that satisfies the melting start condition and the output value of the light-receiving unit 21 at that time, it is preferable to increase the difference in absorption coefficient of the semiconductor wafer 35 at the peak sensitivity wavelengths of the two light-receiving units 21. For example, it is preferable to set the peak sensitivity wavelengths of the two light-receiving units 21 so as to satisfy the condition that the larger absorption coefficient is at least twice the smaller absorption coefficient.

[0041] When the semiconductor wafer 35 is made of silicon, in order to read the temperature information of the outermost surface, it is preferable that the peak sensitivity wavelength of one of the light receiving sections 21 is set to a wavelength that is not transparent to silicon, for example, 1 μm or less. For example, it is preferable that the peak sensitivity wavelength is set to a wavelength range of visible light with a wavelength of 400 nm or more and 800 nm or less, or a wavelength range of near-infrared light with a wavelength of about 900 nm.

[0042] FIG. 7 is a flow chart showing a procedure for performing laser annealing on a semiconductor wafer 35 using a laser annealing apparatus equipped with a process monitor according to the embodiment.

[0043] First, a semiconductor wafer 35 (FIG. 1) into which a dopant has been implanted is held on a stage 31 (FIG. 1) (step S1). This procedure is performed by, for example, a robot arm, etc. The stage 31 fixes the semiconductor wafer 35 by, for example, a vacuum chuck.

[0044] After the semiconductor wafer 35 is held on the stage 31, output of a pulsed laser beam from the laser light source 11 and movement of the stage 31 are started (step S2). While the semiconductor wafer 35 is being scanned with the pulsed laser beam, the intensity of the radiated light from the semiconductor wafer 35 is measured by the photodetector 20 (step S3). For example, the processing device 40 acquires the output value of the photodetector 20.

[0045] The processing device 40 associates the position on the surface of the semiconductor wafer 35 where the laser beam is incident with the output value of the photodetector 20, and stores the associated information in the storage device 41 (step S4). The processes of steps S3 and S4 are repeated until almost the entire surface of the semiconductor wafer 35 is annealed (step S5).

[0046] When annealing of almost the entire surface of the semiconductor wafer 35 is completed, the processing device 40 calculates the reached temperature of the outermost surface of the semiconductor wafer 35 based on the output value of the photodetector 20 (step S6). For example, the relationship between the output values ​​of the two light receiving parts 21 and the reached temperature of the outermost surface of the semiconductor wafer 35 is determined in advance and stored in the storage device 41. The processing device 40 outputs the calculated reached temperature of the outermost surface of the semiconductor wafer 35 to the output device 42 (FIG. 1) in association with the position within the surface of the semiconductor wafer 35. For example, the distribution of the reached temperatures within the surface of the semiconductor wafer 35 may be displayed as a diagram.

[0047] By using the process monitor according to the above embodiment, it is possible to obtain with high accuracy the temperature reached by the outermost surface of the semiconductor wafer 35. As a result, it is possible to determine with high accuracy whether or not the outermost surface of the semiconductor wafer 35 has melted.

[0048] Next, a modification of the above embodiment will be described. In the above embodiment, the number of light receiving sections 21 (FIGS. 2A and 2B) included in the photodetector 20 is two, but the photodetector 20 may include three or more light receiving sections 21. By arranging three or more light receiving sections 21 with different peak sensitivity wavelengths, the photodetector 20 can measure the intensity of radiant light in three or more wavelength ranges. This can improve the accuracy of identifying the pulse energy that satisfies the melting start condition and the output value of the light receiving section 21 at that time.

[0049] In the above embodiment, the attained temperature of the outermost surface of the semiconductor wafer 35 is obtained based on the measurement results of the photodetector 20, but it is also possible to obtain other physical quantities related to the semiconductor wafer 35 that change due to annealing. For example, by determining in advance the relationship between the dopant activation rate, sheet resistance, etc. and the measurement results of the photodetector 20, these physical quantities can be obtained based on the measurement results of the photodetector 20.

[0050] In the above embodiment, a semiconductor wafer is the object of annealing, but the process monitor according to the embodiment can be used when a semiconductor member other than a semiconductor wafer is the object of annealing. In the above embodiment, laser annealing is applied as the method for annealing a semiconductor wafer, but other annealing methods may be applied. For example, lamp annealing, furnace annealing, etc. may be applied. In addition, when annealing is performed by a method that generates a temperature distribution in the depth direction, particularly excellent effects can be obtained by using the process monitor according to the above embodiment.

[0051] The above embodiments are illustrative, and it goes without saying that partial replacement or combination of the configurations shown in the embodiments and modifications is possible. Similar effects due to similar configurations of the embodiments and modifications are not mentioned for each embodiment and modification. Furthermore, the present invention is not limited to the above embodiments. For example, it will be obvious to those skilled in the art that various modifications, improvements, combinations, etc. are possible. [Explanation of symbols]

[0052] 10 Laser optics 11 Laser light source 12 Uniformization optical system 13 Folding Mirror 20 Photodetector 21 Light receiving part 22 Optical Sensor 23 Bandpass Filter 25 Dichroic mirror 26 Lenses 30 Chamber 31 Stage 32 Windows 35 Semiconductor Wafers 37 Beam Spot 38 Beam spot image 40 Processing equipment 41 Storage device 42 Output Device 43 Input Devices

Claims

1. a photodetector for separately detecting intensities of a plurality of mutually different wavelength ranges of radiated light from the semiconductor member during annealing; A processing device that determines a physical quantity related to the semiconductor member that changes due to annealing based on the intensities of a plurality of wavelength ranges detected by the photodetector; and having The process monitor is configured so that light in the wavelength range of light for annealing from the semiconductor member is not incident on the photodetector.

2. the photodetector detects radiant light from the semiconductor member, the surface layer of which is heated by the incidence of the laser beam; 2. The process monitor according to claim 1, wherein the processing device determines an attained temperature of an outermost surface of the semiconductor workpiece as a physical quantity related to the semiconductor workpiece that changes due to annealing.

3. A photodetector for separately detecting the intensities of a plurality of mutually different wavelength ranges of radiated light from a semiconductor member during annealing; A processing device that determines a physical quantity related to the semiconductor member that changes due to annealing based on the intensities of a plurality of wavelength ranges detected by the photodetector; and having the photodetector detects radiant light from the semiconductor member, the surface layer of which is heated by the incidence of the laser beam; The processing device determines an attained temperature of the outermost surface of the semiconductor member as a physical quantity related to the semiconductor member that changes due to annealing, a beam spot of the laser beam on the surface of the semiconductor member has an elongated shape that is long in one direction, the photodetector includes a plurality of light receiving units that detect the intensities of radiation in a plurality of wavelength ranges separately; Further, an imaging optical system for forming an image of the surface of the semiconductor member is provided, A process monitor in which the plurality of light receiving sections are arranged at different positions in a longitudinal direction of an image of the beam spot on the surface of the semiconductor member formed by the imaging optical system.

4. The process monitor according to claim 3 , wherein the plurality of light receiving sections each include an optical sensor having a different peak sensitivity wavelength.

5. 4. The process monitor according to claim 3, wherein the plurality of light receiving sections each include an optical sensor having the same spectral sensitivity characteristic and a bandpass filter having a different passing wavelength range, and radiant light transmitted through the bandpass filter is incident on the optical sensor.

6. Annealing the semiconductor member; measuring the intensities of a plurality of mutually different wavelength ranges of the radiated light from the semiconductor member during annealing separately with a photodetector configured so that light in the wavelength range of the annealing light from the semiconductor member is not incident; A process monitoring method for determining a physical quantity related to the semiconductor member that changes due to annealing based on the measurement results.

7. The annealing of the semiconductor member is performed by irradiating a laser beam onto the semiconductor member, The process monitor method according to claim 6, wherein the reached temperature of the outermost surface of the semiconductor workpiece is determined as the physical quantity related to the semiconductor workpiece.

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