Process monitors and process monitoring methods

Abstract

A photodetector detects the intensity of multiple wavelength regions of radiation emitted from the annealing semiconductor component, each region being different from the others. A processing device calculates the physical quantities of the semiconductor component that have changed due to annealing based on the intensities of these wavelength regions detected by the photodetector. Thus, it is possible to measure the physical quantities of the semiconductor component that have changed due to annealing without damaging the semiconductor component.

Description

Technical Field

[0001] This invention relates to a process monitor and process monitoring method for determining the physical quantities of a semiconductor component that change due to annealing. Background Technology

[0002] Previously, as an example of a method to determine the in-plane distribution of the activation state of a semiconductor wafer that has been doped and activated by annealing, surface resistivity was measured. The activation state of the dopant can be evaluated based on the in-plane distribution of the surface resistivity.

[0003] Previous technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2007-81348 Summary of the Invention

[0006] The technical problem to be solved by the invention

[0007] The four-probe method is commonly used in the measurement of surface resistivity. However, surface resistivity measurements using the four-probe method are performed after annealing using a different apparatus than the activation annealing apparatus. Therefore, surface resistivity measurement becomes an offline operation, which is time-consuming and labor-intensive. Furthermore, the probes must contact the semiconductor wafer, which can damage the wafer. Additionally, to determine the quality of the annealing results, the temperature of the semiconductor wafer during annealing must be measured.

[0008] The purpose of this invention is to provide a process monitor and process monitoring method that can measure physical quantities of semiconductor components that change due to annealing without damaging the semiconductor components.

[0009] means for solving technical problems

[0010] According to one aspect of the present invention, a process monitor is provided, which has:

[0011] A photodetector detects the intensity of multiple different wavelength regions of radiated light from semiconductor components during annealing; and

[0012] The processing device determines the physical quantities of the semiconductor component that have changed due to annealing based on the intensity of multiple wavelength regions detected by the photodetector.

[0013] According to another aspect of the present invention, a process monitoring method is provided, wherein,

[0014] Annealing of semiconductor components.

[0015] The intensities of multiple wavelength regions of radiation emitted from the annealed semiconductor component were measured, each distinct from the others.

[0016] The physical quantities of the semiconductor component that have changed due to annealing are determined based on the measurement results.

[0017] Invention Effects

[0018] By detecting the radiation emitted from the semiconductor component, the physical quantities of the semiconductor component that have changed due to annealing can be determined without damaging the semiconductor component. Furthermore, by measuring the intensity of the radiation in multiple wavelength regions separately, the accuracy of the physical quantity measurement can be improved. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a laser annealing apparatus equipped with a process monitor based on an embodiment.

[0020] Figure 2 (A) is a schematic diagram showing a structural example of a photodetector and optical components arranged in the path of the radiated light. Figure 2 (B) is a schematic diagram showing another structural example of a photodetector and optical components arranged in the path of the radiated light.

[0021] Figure 3 This is a diagram illustrating an example of the pulse waveforms of the pulsed laser beam output from a laser source and the output signal waveforms of the two light-receiving parts of a photodetector.

[0022] Figure 4 Figures (A) and (B) are examples of temperature distribution in the depth direction when a laser beam is incident on a semiconductor wafer.

[0023] Figure 5 Figures (A) to (D) show the temperature distribution along the depth direction when the pulse width of the pulsed laser beam is set to constant and the pulse energy is changed.

[0024] Figure 6 It is a graph that curve-fits an example of the output values ​​of two light-receiving parts relative to the pulse energy.

[0025] Figure 7 This is a flowchart illustrating the steps of performing laser annealing on a semiconductor wafer using a laser annealing apparatus equipped with a process monitor based on an embodiment. Detailed Implementation

[0026] refer to Figures 1 to 7 The process monitor and process monitoring method based on the embodiments are described.

[0027] Figure 1This is a schematic diagram of a laser annealing apparatus equipped with a process monitor based on an embodiment. The laser annealing apparatus includes a laser optics system 10, a chamber 30, a photodetector 20, a processing unit 40, a storage unit 41, an output unit 42, and an input unit 43. The function of the process monitor is implemented through the photodetector 20 and the processing unit 40, etc.

[0028] The laser optical system 10 includes a laser source 11, a homogenizing optical system 12, and a reflecting mirror 13. The laser source 11 outputs a laser beam in the infrared region. For example, a laser diode with an excitation wavelength of 808 nm can be used as the laser source 11. The homogenizing optical system 12 homogenizes the beam distribution of the laser beam output from the laser source 11. The reflecting mirror 13 reflects the laser beam that has passed through the homogenizing optical system 12 downwards.

[0029] A window 32 for transmitting a laser beam is provided on the top plate of the chamber 30, and a stage 31 is disposed inside the chamber 30. An object to be annealed (i.e., a semiconductor wafer 35) is held on the stage 31. A dopant is implanted into the surface layer of the semiconductor wafer 35. The dopant implantation is performed, for example, using ion implantation. The dopant is not activated before annealing. For example, a silicon wafer can be used as the semiconductor wafer 35. For example, phosphorus (P), arsenic (As), and boron (B) can be used as the dopant.

[0030] A laser beam output from the laser optical system 10 passes through a beam splitter 25 and a window 32 and is incident on a semiconductor wafer 35 held on a stage 31. Reflectors, lenses, etc., may be arranged along the path of the laser beam as needed. The laser beam spot on the surface of the semiconductor wafer 35 has an elongated shape along one direction, for example, a length of approximately 3 mm to 5 mm and a width of approximately 0.1 mm to 0.3 mm. By incidenting the laser beam on the semiconductor wafer 35, the surface portion of the semiconductor wafer 35 is heated at the beam spot location. The processing apparatus 40 controls the stage 31 to move the semiconductor wafer 35 in two directions parallel to its surface. By scanning the beam spot along its width direction and performing a sub-scan along its length direction on the surface of the semiconductor wafer 35, laser annealing can be performed on almost the entire area of ​​the upper surface of the semiconductor wafer 35.

[0031] If a laser beam is incident on the semiconductor wafer 35, the surface layer at the incident location is heated, and the dopant is activated. Radiation is emitted from the heated portion. A portion of the radiation emitted from the semiconductor wafer 35 is reflected by a beam splitter 25 and incident on the photodetector 20. The beam splitter 25, for example, allows light in wavelengths shorter than 1 μm to pass through and reflects light in wavelengths longer than 1 μm. Lenses, optical filters, etc., may also be configured along the path of the radiation from the semiconductor wafer 35 to the photodetector 20, as needed. The photodetector 20 and the optical components along the path of the radiation will be discussed later. Figure 2 Explanation is provided for (A) and (B).

[0032] The processing device 40 acquires the detection signal output from the photodetector 20 synchronously with each irradiation of the pulsed laser beam. Furthermore, it establishes a correspondence between the magnitude (output value) of the acquired detection signal and the in-plane position of the semiconductor wafer 35, and stores it in the storage device 41. For example, a time waveform of the output value corresponding to the time-varying intensity of the radiated light can be obtained for each irradiation of the pulsed laser beam. The output value stored in the storage device 41 is, for example, the peak value of the time waveform for each irradiation of the pulsed laser beam.

[0033] Various commands or data used to instruct the operation of the process monitor and the laser annealing device are input to the processing unit 40 via the input device 43. The processing unit 40 outputs the monitoring results based on the process monitor to the output device 42.

[0034] Figure 2 (A) is a schematic diagram showing a structural example of a photodetector 20 and optical components disposed along the path of the radiated light. Radiated light is emitted from a region corresponding to the beam point 37 of a pulsed laser beam incident on the surface of a semiconductor wafer 35. The emitted radiated light passes through two lenses 26 and then enters the photodetector 20. For example, one of the two lenses 26 is disposed in a beam splitter 25 (…). Figure 1 One lens is positioned between the beam splitter 25 and the photodetector 20, while the other is positioned between the beam splitter 25 and the photodetector 20. The two lenses 26 constitute an imaging optical system that images the beam point 37 on the surface of the semiconductor wafer 35 at the location where the photodetector 20 is positioned. That is, the surface of the semiconductor wafer 35 and the light-receiving surface of the photodetector 20 have an object plane and image plane relationship.

[0035] The light detector 20 includes two light-receiving units 21 that detect the intensity of radiated light. The two light-receiving units 21 are located at different positions along the length of the image 38 of the beam point 37. Each light-receiving unit 21 includes a light sensor 22 with different peak sensitivity wavelengths. Each light sensor 22 is sensitive to the infrared wavelength region and outputs a signal (voltage) corresponding to the intensity of the incident radiated light. The signals output from the two light sensors 22 are input to the processing device 40.

[0036] Figure 2 (B) is a schematic diagram showing another structural example of the photodetector 20 and optical components arranged in the path of the radiated light. Figure 2 In the structural example shown in (A), the two light-receiving parts 21 each include a photosensitive sensor 22 with different peak sensitivity wavelengths. In contrast, in Figure 2 In the structural example shown in (B), the two light-receiving units 21 each include a photosensitive sensor 22 with the same spectral sensitivity characteristics and a bandpass filter 23 with different wavelength regions. Radiated light passing through the bandpass filter 23 is incident on the photosensitive sensor 22. Therefore, the peak sensitivity wavelengths of the two light-receiving units 21 become different.

[0037] Figure 3 This is a graph showing an example of the pulse waveforms of the pulsed laser beam output from the laser source 11 and the output signal waveforms of the two light-receiving sections 21 of the photodetector 20. If the laser pulse increases at time t1, the temperature of the surface layer of the semiconductor wafer 35 increases accordingly, and the output value of the light-receiving section 21 gradually increases. If the laser pulse decreases at time t2, the temperature of the surface layer of the semiconductor wafer 35 decreases accordingly, and the output value of the light-receiving section 21 gradually decreases. The peak output intensity Vp of the light-receiving section 21 based on the laser pulses from time t1 to t2 is stored in the storage device 41 corresponding to the light-receiving section 21. Typically, this peak intensity Vp differs between the two light-receiving sections 21.

[0038] Next, refer to Figure 4 (A) Figure 5 Section (D) explains the superior effects of this embodiment.

[0039] Figure 4 Figures (A) and (B) are examples of temperature distribution in the depth direction at the moment of laser pulse descent when a laser beam is incident on a semiconductor wafer 35. Figure 4 In the charts (A) and (B), the horizontal axis represents the depth from the surface of the semiconductor wafer at 35°C, and the vertical axis represents the temperature. Figure 4 The solid and dashed lines in (A) and (B) represent the temperature distribution when laser pulses with the same energy but relatively longer and shorter pulse widths are incident, respectively.

[0040] With the same pulse energy, a shorter pulse width results in a higher peak power. Therefore, the surface temperature TS (at depth zero) is higher with a shorter pulse width than with a longer pulse width. If the pulse width increases, the heat transferred to the depth direction during laser pulse incidence increases. Conversely, if the pulse width decreases, the heat transferred to the depth direction during laser pulse incidence decreases. Regardless of pulse width, the temperature decreases with increasing depth; however, the shorter the pulse width, the less heat is transferred to the depth direction, thus the temperature decrease is greater with shorter pulse widths. Therefore, in regions deeper than a certain depth Da, the temperature with a longer pulse width is higher than the temperature with a shorter pulse width.

[0041] The radiation emitted from the outermost surface is not absorbed by the semiconductor wafer 35 and reaches the photodetector 20. Conversely, a portion of the radiation emitted from deeper regions is absorbed by the semiconductor wafer 35 itself before reaching the photodetector 20. The amount of absorption depends on the absorption coefficient of the semiconductor wafer 35, which in turn depends on the wavelength. Radiation with a high absorption coefficient in the wavelength range is less likely to be emitted from the deeper regions of the semiconductor wafer 35 to the outside.

[0042] In the following description, the absorption phenomenon of radiated light is simplified by assuming that one of the light-receiving parts 21 detects radiated light emitted from a region shallower than depth D1, and the other light-receiving part 21 detects radiated light emitted from a region shallower than depth D2 (D2 < D1).

[0043] like Figure 4 As shown in (A), the detection value of one of the light-receiving parts 21 changes according to the area of ​​the shaded portion in a region shallower than depth D1. Figure 4 As shown in (B), the detection value of the other light-receiving part 21 changes according to the area of ​​the shaded part of the region that is shallower than depth D2.

[0044] exist Figure 4 In the example shown in (A), in the region shallower than Da, the area of ​​the temperature distribution with a short pulse width is greater than the area of ​​the temperature distribution with a long pulse width, and the difference is A. However, in the region from Da to D1, the area of ​​the temperature distribution with a long pulse width is greater than the area of ​​the temperature distribution with a short pulse width, and the difference is B. If area A and area B are equal, then the area S11 of the temperature distribution graph with a long pulse width is almost equal to the area S12 of the temperature distribution graph with a short pulse width. Therefore, it is impossible to distinguish based solely on the detection value of the light-receiving part 21 that detects radiation light from a region shallower than D1. Figure 4 The solid line in (A) represents the temperature distribution, while the dashed line represents the temperature distribution. Therefore, it is difficult to accurately determine the highest temperature reached on the outermost surface of the semiconductor wafer 35.

[0045] In contrast, Figure 4 In the example shown in (B), in the region from depth Da to D2, the area of ​​the temperature distribution with a longer pulse width is larger than the area of ​​the temperature distribution with a shorter pulse width, and the difference is C. Area C is smaller than area A. Therefore, the area S21 of the temperature distribution graph with a longer pulse width is smaller than the area S22 of the temperature distribution graph with a shorter pulse width. Since areas S21 and S22 are different, the distribution can be distinguished based on the detection value of the light-receiving part 21 that detects radiation light from a region shallower than D2. Figure 4 The temperature distribution of the solid line and the temperature distribution of the dashed line in (B).

[0046] By using two light-receiving sections 21 to measure the intensity of radiation light in different wavelength regions, as in this embodiment, the surface temperature of the semiconductor wafer 35 with different temperature distributions in the depth direction can be measured more accurately.

[0047] Figure 5 Figures (A) to (D) show the temperature distribution along the depth direction when the pulse width of the pulsed laser beam is set to constant and the pulse energy is changed. Figure 5 In the charts (A) to (D), the horizontal axis represents the depth from the surface of the semiconductor wafer at 35°C, and the vertical axis represents the temperature.

[0048] Figure 5 Figures (A) and (B) show the temperature distribution when a single pulsed laser beam is applied to the semiconductor wafer 35 at pulse energies E1 and E2 (E1 < E2) where the temperature at the outermost surface does not exceed the melting point. The outermost surface has the highest temperature, which decreases with increasing depth. If the pulse energy increases from E1 to E2, the temperature at all depths of the semiconductor wafer 35 will rise, but the shape of the temperature distribution remains almost unchanged.

[0049] The peak intensity Vp of the signal output from the light-receiving part 21 that detects radiation from a region shallower than D1. Figure 3 Under the condition of pulse energy E1, it becomes equivalent to area S11 ( Figure 5 The size of (A) becomes equivalent to the area S11 in the case of pulse energy E2. Figure 5 (A) and increment ΔS11 ( Figure 5 The magnitude of the sum of (A)). The peak intensity Vp of the signal output from the light-receiving part 21 that detects radiation light from a region shallower than D2. Figure 3 Under the condition of pulse energy E1, it becomes equivalent to area S21 ( Figure 5 The size of (B) becomes equivalent to the area S21 in the case of pulse energy E2. Figure 5 (B) and increment ΔS21 Figure 5The magnitude of the sum of (B)).

[0050] Figure 5 In diagrams (C) and (D), the temperature distribution under single-pulse laser irradiation occurs when the surface temperature of the semiconductor wafer 35 reaches above its melting point using pulse energies E3 and E4 (E3 < E4). At pulse energy E3, the surface temperature of the semiconductor wafer 35 reaches its melting point. At pulse energy E4, the surface layer of the semiconductor wafer 35 melts. If the surface layer of the semiconductor wafer 35 begins to melt, the surface temperature remains almost constant at the melting point. Therefore, the surface temperature is almost the same at pulse energies E3 and E4. The temperature of the unmelted deeper regions increases with increasing pulse energy; therefore, the temperature at pulse energy E4 is higher than the temperature at pulse energy E3.

[0051] The peak intensity Vp of the signal output from the light-receiving part 21 that detects radiation from a region shallower than D1. Figure 3 Under pulse energy E3, it becomes equivalent to area S11 ( Figure 5 The size of (C) becomes equivalent to the area S11 in the case of pulse energy E4. Figure 5 (C) and increment ΔS11 ( Figure 5 The magnitude of the sum of (C)). The peak intensity Vp of the signal output from the light-receiving part 21 that detects radiation light from a region shallower than D2. Figure 3 Under pulse energy E3, it becomes equivalent to area S21 ( Figure 5 The size of (D) becomes equivalent to the area S21 in the case of pulse energy E4. Figure 5 (D) and increment ΔS21 ( Figure 5 The magnitude of the sum of (D)). Furthermore, due to simplification, the difference between the emissivity of a semiconductor in the molten state and that in the solid state is not considered here.

[0052] If the outermost surface of the semiconductor wafer 35 begins to melt, even with increased pulse energy, the temperature of the outermost surface will hardly rise. Therefore, the ratio of the increment ΔS11 to the area S11 ( Figure 5 The ratio of the middle (C) and the increment ΔS21 to the area S21 ( Figure 5 The proportion of (D) in the middle will become smaller than that in the unmelted state. Figure 5 (A) and (B)). That is, the slope of the change in the output value of the light-receiving section 21 relative to the increase in pulse energy becomes gradual. It can be considered that the pulse energy at which this slope begins to gradually decrease is the energy condition for the onset of melting. In order to perform annealing at the highest possible temperature without melting the semiconductor wafer 35, it is necessary to accurately determine this energy condition for the onset of melting.

[0053] Figure 6 This is a graph that shows the distribution of output values ​​of the two light-receiving sections 21 relative to the pulse energy. The detection values ​​of the light-receiving section 21, which detects radiation light from regions shallower than D1 and D2, are represented by the thick curve D1 and the thin curve D2, respectively.

[0054] exist Figure 6 In the distribution graph shown, melting begins at a pulse energy of E1. Near the point where melting begins, the slope of the graph begins to change, but no clear inflection point appears. Therefore, it is difficult to accurately determine the melting initiation condition based on measurements from a single light-receiving section 21.

[0055] After melting begins, the increment ΔS11( Figure 5 (C) and ΔS21 Figure 5 (D) and area S11 ( Figure 5 (C) and S21 Figure 5 The ratio of (D) to the increment ΔS11 before melting begins is smaller than the increment ΔS11 before melting begins. Figure 5 (A) and ΔS21 Figure 5 (B) and area S11 Figure 5 (A) and S21 Figure 5 The ratio of (B) to (D2). Therefore, if the pulse energy exceeds E1, the slope of the graph will slow down. However, the ratio of increment ΔS21 to area S21 decreases to a greater extent than the ratio of increment ΔS11 to area S11. This is because the temperature rise in regions shallower than depth D2 is suppressed. Therefore, in Figure 6 In the graph shown, when the pulse energy exceeds E1, the slope of the graph becomes less steep on curve D2 than on curve D1.

[0056] Because the slopes of curves D1 and D2 decrease to different degrees, by comparing the changes in the output values ​​of the two light-receiving sections 21 when the pulse energy is changed, the pulse energy at which the conditions for starting melting are met and the output value of the light-receiving section 21 at that time can be determined more accurately. For example, based on the relationship between the difference between the value displayed as curve D1 and the value displayed as curve D2 relative to the pulse energy and the pulse energy, the pulse energy E1 at the moment of melting start can be determined more accurately.

[0057] To improve the accuracy of determining the pulse energy that satisfies the melting start condition and the output value of the light-receiving section 21 at this time, it is preferable to increase the difference in absorption coefficients of the semiconductor wafer 35 at the peak sensitivity wavelength between the two light-receiving sections 21. For example, it is preferable to set the peak sensitivity wavelength of the two light-receiving sections 21 to satisfy the condition that the larger absorption coefficient is more than twice the smaller absorption coefficient.

[0058] When the semiconductor wafer 35 is silicon, in order to read the temperature information of the outermost surface, it is preferable to set the peak sensitivity wavelength of one of the light-receiving parts 21 to a wavelength that is opaque to silicon, for example, less than 1 μm. For example, it is preferable to set it to the wavelength region of visible light with a wavelength of 400 nm or more and less than 800 nm, or the wavelength region of near-infrared light with a wavelength of around 900 nm.

[0059] Figure 7 This is a flowchart illustrating the steps of performing laser annealing on a semiconductor wafer 35 using a laser annealing apparatus equipped with a process monitor based on the embodiment.

[0060] First, the semiconductor wafer 35 implanted with dopant is... Figure 1 ) Keep it on workbench 31 ( Figure 1 (Step S1). This step is performed by a robotic arm or the like. The worktable 31 uses, for example, a vacuum chuck to hold the semiconductor wafer 35.

[0061] After holding the semiconductor wafer 35 on the stage 31, the output of the pulsed laser beam from the laser source 11 and the movement of the stage 31 are initiated (step S2). During the scanning of the semiconductor wafer 35 using the pulsed laser beam, the intensity of the radiated light from the semiconductor wafer 35 is measured using a photodetector 20 (step S3). For example, the processing device 40 acquires the output value of the photodetector 20.

[0062] The processing device 40 establishes a corresponding association between the position of the semiconductor wafer 35 with which the laser beam is incident and the output value of the photodetector 20, and then saves it in the storage device 41 (step S4). The processing steps S3 and S4 are repeated until almost the entire surface area of ​​the semiconductor wafer 35 is annealed (step S5).

[0063] If annealing is completed over almost the entire surface area of ​​the semiconductor wafer 35, the processing device 40 calculates the arrival 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 arrival temperature of the outermost surface of the semiconductor wafer 35 is pre-determined and stored in the storage device 41. The processing device 40 establishes a corresponding association between the calculated arrival temperature of the outermost surface of the semiconductor wafer 35 and the position within the surface of the semiconductor wafer 35, and then outputs it to the output device 42. Figure 1 For example, it is preferable to display the distribution of the arrival temperature within the plane of the semiconductor wafer 35 in graphical form.

[0064] By using a process monitor based on the above embodiment, the temperature reached at the outermost surface of the semiconductor wafer 35 can be determined more accurately. Therefore, it is possible to accurately determine whether the outermost surface of the semiconductor wafer 35 has melted.

[0065] Next, variations of the above embodiments will be described.

[0066] In the above embodiments, the light-receiving part 21 included in the light detector 20 ( Figure 2 The number of (A) and (B) is two, but it can also be configured such that the photodetector 20 includes three or more light-receiving units 21. By configuring three or more light-receiving units 21 with different peak sensitivity wavelengths, the photodetector 20 can measure the intensity of radiation light in three or more wavelength regions. As a result, the accuracy of determining the pulse energy that satisfies the melting start condition and the output value of the light-receiving unit 21 at this time can be improved.

[0067] In the above embodiment, the arrival temperature of the outermost surface of the semiconductor wafer 35 is determined based on the measurement results of the photodetector 20. However, other physical quantities of the semiconductor wafer 35 that change due to annealing can also be determined. For example, by pre-determining the relationship between the activation rate of the dopant or the surface resistance and the measurement results of the photodetector 20, these physical quantities can be determined based on the measurement results of the photodetector 20.

[0068] In the above embodiments, a semiconductor wafer was used as the annealing target. However, when other semiconductor components besides semiconductor wafers are used as the annealing target, the process monitor based on the embodiments can also be used. Furthermore, in the above embodiments, laser annealing was used as the annealing method for semiconductor wafers, but other annealing methods can also be used. For example, lamp annealing, furnace annealing, etc., can be used. Additionally, when annealing is performed using a method that generates a temperature distribution in the depth direction, particularly excellent results can be obtained by using the process monitor based on the above embodiments.

[0069] The above embodiments are examples, and naturally, parts of the structures shown in the embodiments and modifications can be replaced or combined. The same effects based on the same structure in the embodiments and modifications are not mentioned one by one in the embodiments and modifications. Moreover, the present invention is not limited to the above embodiments. For example, various changes, improvements, combinations, etc., can be made, which will be obvious to those skilled in the art.

[0070] Symbol Explanation

[0071] 10-Laser optical system, 11-Laser source, 12-Homogeneous optical system, 13-Reflecting mirror, 20-Photodetector, 21-Light receiving unit, 22-Photosensor, 23-Bandpass filter, 25-Beam splitter, 26-Lens, 30-Cavity, 31-Stage, 32-Window, 35-Semiconductor wafer, 37-Beam point, 38-Image of beam point, 40-Processing device, 41-Storage device, 42-Output device, 43-Input device.

Claims

1. A process monitor, characterized in that, have: A photodetector detects the intensity of multiple different wavelength regions of radiated light from semiconductor components during annealing; and The processing device determines the physical quantities of the semiconductor component that have changed due to annealing based on the intensity of multiple wavelength regions detected by the photodetector. The photodetector includes multiple light-receiving units that detect the intensity of radiated light in multiple wavelength regions. One of the plurality of light-receiving parts detects radiation emitted from a region shallower than depth D1, and another light-receiving part detects radiation emitted from a region shallower than depth D2, where D2 < D1.

2. The process monitor according to claim 1, characterized in that, The photodetector detects the radiation light from the semiconductor component whose surface has been heated due to the incident laser beam. The processing device determines the temperature reached at the outermost surface of the semiconductor component as a physical quantity relating to the semiconductor component that changes due to annealing.

3. The process monitor according to claim 2, characterized in that, The laser beam spot on the surface of the semiconductor component has an elongated shape along one direction. The process monitor also includes an imaging optical system that images the surface of the semiconductor component. The multiple light-receiving parts are arranged at different positions along the length direction of the image formed by the imaging optical system on the surface of the semiconductor component, where the light beam points are located.

4. The process monitor according to any one of claims 1 to 3, characterized in that, The plurality of light-receiving units include optical sensors with different peak sensitivity wavelengths.

5. The process monitor according to any one of claims 1 to 3, characterized in that, The plurality of light-receiving parts include photosensitive sensors with the same spectral sensitivity characteristics and bandpass filters with different wavelength regions, and the radiated light passing through the bandpass filters is incident on the photosensitive sensors.

6. A process monitoring method, characterized in that, Annealing of semiconductor components. The intensities of multiple wavelength regions, distinct from each other, of the radiation emitted from the semiconductor component during annealing, from regions shallower than depth D1 and from regions shallower than depth D2, are measured, where D2 < D1. The physical quantities of the semiconductor component that have changed due to annealing are determined based on the measurement results.

7. The process monitoring method according to claim 6, characterized in that, The annealing of the semiconductor component is performed by incidenting a laser beam onto the semiconductor component. The temperature reached at the outermost surface of the semiconductor component is determined as a physical quantity relating to the semiconductor component.

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