Laser processing device and laser monitoring method

Abstract

The present invention provides a laser processing device and a laser processing method capable of forming a high-quality semiconductor film. The ELA device (excimer laser annealing device) (1) includes: a laser oscillator (10) that generates laser light for forming a polycrystalline silicon film by irradiating an amorphous silicon film to be processed on a substrate with the laser light; a pulse measuring instrument (100) that detects a first portion of light and a second portion of light contained in the laser light; and a monitoring device (60) that compares the detection result of the first portion of light with the detection result of the second portion of light.

Description

Technical Field

[0001] The invention relates to a laser processing device and a laser monitoring method. Background Art

[0002] Laser annealing apparatuses are known that irradiate an amorphous film formed on a silicon substrate, a glass substrate, etc. with laser light to crystallize the amorphous film and form a crystalline film. For example, Patent Document 1 describes a related laser annealing apparatus.

[0003] Reference List

[0004] Patent Literature

[0005] Patent document 1: Japanese patent JP5829575.

[0006] Technical issues

[0007] In a laser processing apparatus, such as a laser annealing apparatus, it is desirable to irradiate an object to be processed with appropriate laser light in order to form a high-quality semiconductor film. Summary of the invention

[0008] Other problems and novel features will become apparent from the description of this specification and the accompanying drawings.

[0009] Solution to the problem

[0010] According to an embodiment, a laser processing device includes: a laser generating device configured to generate a laser applied to an object to be processed; a photoelectric detection device configured to detect a first portion of light and a second portion of light contained in the laser; and a monitoring unit configured to compare the detection result of the first portion of light with the detection result of the second portion of light.

[0011] According to an embodiment, the laser monitoring method includes: step (A), generating a laser applied to an object to be processed; step (B), detecting a first portion of light and a second portion of light contained in the laser; and step (C), comparing the detection result of the first portion of light with the detection result of the second portion of light.

[0012] Beneficial effects of the present invention

[0013] According to the aforementioned embodiments, a high-quality semiconductor film can be formed. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a diagram showing one structural example of a laser annealing apparatus according to the first embodiment.

[0015] Figure 2 is a diagram showing another structural example of the laser annealing apparatus according to the first embodiment.

[0016] Figure 3 FIG. 1 is a diagram schematically showing the state of a crystal film formed by a laser annealing apparatus.

[0017] Figure 4A It is a diagram showing the relationship of laser light in a laser annealing device.

[0018] Figure 4B It is a diagram showing the relationship of laser light in a laser annealing device.

[0019] Figure 5 is a side view showing a schematic structure of a pulse measuring instrument of a comparative example.

[0020] Figure 6 is a perspective view showing a schematic structure of a pulse measuring instrument of a comparative example.

[0021] Figure 7 is a side view showing a schematic structure of the pulse measuring instrument according to the first embodiment.

[0022] Figure 8 is a perspective view showing a schematic structure of a pulse measurement instrument according to the first embodiment.

[0023] Fig. 9 is a flowchart showing a pulse waveform monitoring method according to the first embodiment.

[0024] Fig.10 is a diagram showing one example of a pulse waveform monitored by the pulse waveform monitoring method according to the first embodiment.

[0025] Fig.11 is a diagram showing the measurement results of the pulse waveform.

[0026] Fig.12 is a diagram showing the evaluation results of the pulse waveform.

[0027] Fig.13 is a diagram showing the evaluation results of the pulse waveform.

[0028] Fig.14 is a side view showing a schematic structure of a pulse measuring instrument according to the second embodiment.

[0029] Fig.15 is a perspective view showing a schematic structure of a pulse measuring instrument according to a second embodiment.

[0030] Fig.16 : is a front view showing a schematic structure of a slit portion used in the pulse measuring instrument according to the second embodiment.

[0031] Fig.17is a side view showing a schematic structure of a pulse measuring instrument according to the second embodiment.

[0032] Fig.18 is a side view showing a schematic structure of a pulse measuring instrument according to the second embodiment.

[0033] Fig.19 is a side view showing a schematic structure of a pulse measuring instrument according to a modified example.

[0034] Fig. 20 is a side view showing a schematic structure of a pulse measuring instrument according to a third embodiment.

[0035] Fig.21 is a perspective view showing a schematic structure of a pulse measurement instrument according to a third embodiment.

[0036] Fig. 22 : is a front view showing a schematic structure of a slit portion used in the pulse measuring instrument according to the third embodiment.

[0037] Fig.23 1 is a process cross-sectional view showing a method for manufacturing a semiconductor device according to still another embodiment.

[0038] Fig.24 1 is a process cross-sectional view showing a method for manufacturing a semiconductor device according to another embodiment.

[0039] Fig.25 1 is a process cross-sectional view showing a method for manufacturing a semiconductor device according to another embodiment.

[0040] Fig.26 1 is a process cross-sectional view showing a method for manufacturing a semiconductor device according to another embodiment.

[0041] Fig. 27 1 is a process cross-sectional view showing a method for manufacturing a semiconductor device according to another embodiment. DETAILED DESCRIPTION

[0042] The embodiments will be described below with reference to the accompanying drawings. For the sake of clarity of explanation, the following description and drawings are appropriately omitted or simplified. In addition, in each of the drawings, the same reference numerals are used to represent the same elements, and repeated descriptions thereof are omitted as needed.

[0043] (First Embodiment)

[0044] First, a laser processing apparatus and a laser monitoring method according to a first embodiment will be described. The laser processing apparatus according to the first embodiment is, for example, an excimer laser anneal (ELA) apparatus for forming a low temperature poly-silicon (LTPS) film.

[0045] <Structure of the ELA apparatus>

[0046] Reference will be made to Figure 1 describe the structure of the ELA apparatus 1 according to the present embodiment. Figure 1 is a diagram showing the structure of the ELA apparatus 1. The ELA apparatus 1 irradiates the silicon film 201 formed on the substrate 200 with the laser L3. As a result, the amorphous silicon film (a-Si film) 201 can be converted into a polycrystalline silicon film (p-Si film) 201. The substrate 200 is a transparent substrate such as a glass substrate.

[0047] In Figure 1 the shown XYZ three-dimensional Cartesian coordinate system, the Z direction is the vertical direction and is perpendicular to the substrate 200. The XY plane is a plane parallel to the plane on which the silicon film 201 with the substrate 200 formed thereon is located. For example, the X direction is the longitudinal direction of the rectangular substrate 200, and the Y direction is the lateral direction of the substrate 200. Note that when using a θ-axis stage that can rotate from 0° to 90° around the Z axis, the X direction can be the lateral direction of the substrate 200, and the Y direction can be the longitudinal direction of the substrate 200.

[0048] As Figure 1 shown, the ELA apparatus 1 includes an annealing optical system 2, a laser irradiation chamber 50, a pulse measuring instrument 100, a monitoring device 60, and a control device 70. Figure 1 The structure is an example, and in order to perform the monitoring method according to the embodiment, the ELA apparatus 1 may at least include, for example, Figure 2 shown laser oscillator 10, pulse measuring instrument 100, and monitoring device 60.

[0049] The laser irradiation chamber 50 houses a base 52 and a stage 51 provided on the base 52. In the ELA apparatus 1, the silicon film 201 is irradiated with the laser L3 while the substrate 200 is conveyed in the +X direction by the stage 51. In Figure 1 , for the silicon film 201, the silicon film 201 is called an amorphous silicon film 201a before being irradiated with the laser L3, and the silicon film 201 is called a polycrystalline silicon film 201b after being irradiated with the laser L3.

[0050] The annealing optical system 2 is an optical system for generating laser light for crystallizing the amorphous silicon film 201a and irradiating the silicon film 201 with the laser light. Specifically, the annealing optical system 2 includes a laser oscillator 10, an input optical system 20, a beam shaper 30, and an epi-illumination mirror 40.

[0051] The laser oscillator 10 is a laser generating device for generating a pulsed laser as a laser applied to the amorphous silicon film 201a (object to be processed). The generated laser is a laser for crystallizing the amorphous film on the substrate to form a crystalline film, and is, for example, a gas laser. In the present embodiment, an excimer laser with a central wavelength of 308nm is used as an example of a gas laser. The gas laser is not limited to the excimer laser, but may be other gas lasers, such as a CO2 laser. A gas (such as chlorine) is filled in the chamber of the laser oscillator 10, and two resonant cavity mirrors 11 and 12 are arranged to face each other with the gas in between. The resonant cavity mirror 11 is a total reflection mirror for reflecting all light, and the resonant cavity mirror 12 is a partial reflection mirror for transmitting a portion of the light. The gas light L0 excited by the gas is repeatedly reflected between the resonant cavity mirror 11 and the resonant cavity mirror 12, and the amplified light is emitted from the resonant cavity mirror 12 as laser light L1. For example, the laser oscillator 10 repeatedly emits the pulse laser light L1 at a cycle of 500 Hz to 600 Hz. The laser oscillator 10 emits the laser light L1 to the input optical system 20 .

[0052] The input optical system 20 transmits the laser light L1 generated by the laser oscillator 10 to the beam shaper 30. The input optical system 20 includes, for example, a reflector 21 and a reflector 22. The reflector 21 and the reflector 22 may be total reflectors or partial reflectors. The laser light L1 incident from the laser oscillator 10 is reflected by the reflector 21 and the reflector 22 in this order and then emitted to the beam shaper 30.

[0053] The beam shaper 30 shapes the laser light L1 incident via the input optical system 20 to generate the laser light L2 having a beam shape suitable for irradiating the silicon film 201. The beam shaper 30 generates a linear line beam in the Y direction, and further divides the line beam into a plurality of beams (partial light) in the Z direction. In other words, the laser light L2 includes a plurality of line beams arranged in the Z direction. The beam shaper 30 is an optical system for shaping the laser light L1 into a line beam, and is also an optical system for dividing the laser light L1 into a plurality of beams (divided beams). The generation of a plurality of line beams can be performed in the following manner, that is, a line beam is generated by the laser light L1, and then the line beam is divided, or the laser light L1 is divided, and then a line beam is generated from the divided light. For example, the beam shaper 30 expands the laser light L1 in the Y direction by a plurality of cylindrical lenses to convert it into a line beam. In addition, the beam shaper 30 divides one beam into a plurality of beams, for example, by an average divider composed of a lens array. By dividing into a plurality of beams, the steepness width in the beam shape of the laser light to be used for irradiation can be made sharp. For example, the laser light L1 is divided into 11 beams. The beam shaper 30 emits the generated laser light L2 to the epi-mirror 40 .

[0054] The epi-mirror 40 is a rectangular reflecting mirror extending in the Y direction, and reflects the laser light L2, which is a plurality of line beams generated by the beam shaper 30. For example, the epi-mirror 40 is a dichroic mirror, which is a partial reflecting mirror for transmitting a portion of light. In other words, the epi-mirror 40 reflects the laser light L2 to generate the laser light L3, while allowing a portion of the laser light L2 to be transmitted therethrough to generate the laser light L4. The epi-mirror 40 irradiates the silicon film 201 on the substrate 200 with the laser light L3 as reflected light, and emits the laser light L4 as transmitted light to the pulse measurement instrument 100.

[0055] Figure 3 The silicon film 201 to be crystallized by irradiation of the laser L3 is schematically shown. The laser L3 includes a plurality of line beams as described above, and forms a linear irradiation area on the substrate 200 along the Y direction. In other words, the laser L3 irradiated on the substrate 200 forms a linear irradiation area, in which the Y direction is set as the longitudinal direction (long axis direction) and the X direction is set as the lateral direction (short axis direction). In addition, while the substrate 200 is transported in the +X direction by the stage 51, the silicon film 201 is irradiated with the laser L3, whereby a band-shaped area whose width corresponds to the length of the irradiation area along the Y direction can be irradiated with the laser L3. The amorphous silicon film 201a is crystallized by the irradiation of the laser L3 described above. The silicon film 201 is irradiated with the laser L3 while changing the irradiation position of the laser L3 relative to the substrate 200. The substrate 200 is transported in the +X direction by the stage 51, whereby the polycrystalline silicon film 201b is formed in sequence starting from the area irradiated by the laser L3 on the substrate 200.

[0056] Here, the state of the polysilicon film 201b thus formed has a great influence on the performance of the semiconductor device to be manufactured. Therefore, it is required that the crystal state of the polysilicon film 201b is not uneven, that is, Figure 3 As shown in (a), the change in the crystal state is small and uniform. When the crystal state of the polysilicon film 201b is not uniform, that is, Figure 3 (b) shows that the variation of the crystal state is large and non-uniform, and the semiconductor device will be a defective product. Examples of the non-uniformity of the polysilicon film 201b may include the formation of bright stripes and dark stripes (referred to as irradiation non-uniformity) along the irradiation area of ​​the line beam on the polysilicon film 201b. This non-uniformity may be caused by a variation in the spatial distribution of the laser light, i.e., a variation in the light in the beam cross section (referred to as spatial variation). Therefore, in this embodiment, by monitoring the spatial variation of the laser light, the occurrence of non-uniformity in the polysilicon film 201b to be formed can be suppressed.

[0057] Note that solid-state lasers have high coherence and are less likely to cause spatial variations, whereas gas lasers have low coherence and may cause spatial variations. Therefore, this embodiment is applicable to gas lasers, particularly excimer lasers.

[0058] Figure 1 The pulse measuring instrument 100, the monitoring device 60 and the control device 70 in the embodiment are configured to monitor the spatial variation of the laser and control the monitored spatial variation. The pulse measuring instrument 100 and the monitoring device 60 can be used as a measuring unit for measuring the pulse waveform of the laser. In addition, the monitoring device 60 and the control device 70 can be replaced by a processing device having two functions.

[0059] The pulse measurement instrument 100 is a measuring device (photodetection device) for measuring (detecting) the pulse waveform of the laser light to be applied to the substrate 200. In this example, the pulse measurement instrument 100 measures the laser light L4 transmitted from the epi-mirror 40. The pulse measurement instrument 100 measures the intensity of a plurality of light beams (e.g., the first partial light and the second partial light) contained in the laser light L4, and outputs the measurement result to the monitoring device 60. Since it is only necessary to measure the spatial variation of the laser light applied to the substrate 200, the pulse measurement instrument 100 can measure the laser light at other points in the annealing optical system 2. For example, the laser light transmitted through the reflective mirror 21 or the reflective mirror 22 can be measured.

[0060] The monitoring device 60 and the control device 70 may be devices dedicated to the ELA device 1, or may be general-purpose computer devices such as personal computers and server computers. In such devices, the functions of the monitoring device 60 and the control device 70 are implemented by executing a predetermined program stored in a storage unit by a processor (such as a CPU, a central processing unit). Each of the monitoring device 60 and the control device 70 may be implemented by one device, or may be implemented by a plurality of devices on a network.

[0061] The monitoring device 60 is connected to the pulse measuring instrument 100 and the control device 70 so that various information and signals can be input and output therebetween. The monitoring device (monitoring unit) 60 monitors the spatial variation of the laser (the laser L4 in this example) by comparing the input measurement results of the pulse measuring instrument 100. The monitoring device 60 generates a pulse waveform of the laser L4 from the intensity of the laser L4 measured by the pulse measuring instrument 100. The monitoring device 60 generates a pulse waveform of a plurality of light beams contained in the laser L4, and calculates an evaluation parameter for evaluating the pulse waveform. The monitoring device 60 compares the pulse waveforms and the evaluation parameters of the plurality of light beams in the laser L4, and determines the difference therebetween. The monitoring device 60 includes a display unit such as a display, on which the pulse waveform, intensity, etc. of the laser L4 are displayed. The monitoring device 60 determines whether there is a spatial variation in the laser L4 based on the comparison result of the pulse waveform, and outputs the determination result to the control device 70.

[0062] The control device (control unit) 70 is connected to the monitoring device 60 and the laser oscillator 10 so that various information and signals can be input and output between them. The control device 70 performs feedback control on the laser oscillator 10 based on the input determination result of the monitoring device 60. The control device 70 controls the generation conditions of the laser to suppress the spatial variation of the laser. For example, the control device 70 adjusts the angle of the resonant cavity mirror 12 by controlling the servo motor for driving the resonant cavity mirror 12 in the laser oscillator 10, thereby controlling the intensity of the spatial distribution of the laser L1. The control device 70 can automatically control the resonant cavity mirror 12 according to the determination result of the monitoring device 60, or can control the resonant cavity mirror 12 according to the operation of the operator.

[0063] Figure 4A and Figure 4B 1 shows the relationship in spatial distribution (beam shape) between the laser light L1 emitted from the resonant cavity mirror 12 of the laser oscillator 10 and the laser light L2 incident on the incident mirror 40. Figure 4A As shown, the laser light L1 has a shape similar to that of the resonant cavity reflector 12, that is, a substantially rectangular spatial distribution, the longitudinal direction of which corresponds to the Z direction. Figure 4BAs shown, the laser light L2 has a shape similar to that of the incident mirror 40, that is, a substantially rectangular spatial distribution, the longitudinal direction of which corresponds to the Y direction. In other words, the laser light L2 has a beam shape that is rotated 90° around the optical axis relative to the laser light beam L1. Figure 4A The light from the position ZA1 on the +Z side to the position ZB1 on the -Z side in the laser L1 is generated in Figure 4B The light (line beam) from the position YA1 on the +Y side to the position YB1 on the -Y side in the laser L2. Similarly, Figure 4A The light from the laser L1 in the laser beam from the position ZA2 to the position ZB2 is generated in Figure 4B The light from position YA2 to position YB2 in the laser light L2 in the polysilicon film 201b. The unevenness appearing in the polysilicon film 201b, that is, the irradiation unevenness in the Y direction, is caused by the variation in the Z direction in the laser light beam L2 as a factor. Therefore, in the present embodiment, the variation in the Z direction in the laser light L2 (L4 is the transmitted light of L2) is monitored. In addition, in order to adjust the intensity of the light in the Y direction of the laser light L1 corresponding to the space in the Z direction of the laser light L2, the resonant cavity reflection mirror 12 is rotated around the center Y0 in the Y direction to control its angle.

[0064] <Comparative Example Pulse Measurement Instrument>

[0065] Here, in order to deepen the understanding of this embodiment, reference will be made to Figure 5 and Figure 6 The structure of a pulse measuring instrument 900 of a comparative example before applying the present embodiment is described. Figure 5 is a side view showing a schematic structure of a pulse measuring instrument 900, Figure 6 is a perspective view showing a schematic structure of the pulse measuring instrument 900. Figure 5 and Figure 6 As shown, the pulse measuring instrument 900 includes a photodetector 901 and a focusing lens 902 .

[0066] For example, the condenser lens 902 and the photodetector 901 are disposed near the center in the Y direction of the epi-mirror 40. The condenser lens 902 condenses the laser light L4 transmitted through the epi-mirror 40 onto the light receiving portion of the photodetector 901. The photodetector 901 detects the intensity of the laser light L4 condensed by the condenser lens 902.

[0067] As described above, in the pulse measurement instrument 900 of the comparative example, all the beams of the laser light L4 are detected collectively by one photodetector 901. In this example, the laser light L2 and the laser light L4 include the beams B1 to B11, and the photodetector 901 detects all the beams B1 to B11 of the converged laser light L4. However, when all the laser light is detected by one detector as in the pulse measurement instrument 900 of the comparative example, even if there are variations between the beams, the variations are averaged, which makes it impossible to detect spatial variations.

[0068] <Pulse Measurement Device of First Embodiment>

[0069] Will refer to Figure 7 and Figure 8 The structure of the pulse measurement instrument 100 according to the present embodiment will be described. Figure 7 is a side view showing a schematic structure of a pulse measuring instrument 100, Figure 8 1 is a perspective view showing a schematic structure of the pulse measuring instrument 100. Figure 7 and Figure 8 As shown, the pulse measuring instrument 100 includes a plurality of photodetectors 101 and a plurality of condensing lenses 102. For example, the photodetectors 101 are biplanar tubes or photodiodes, and the condensing lenses 102 are cylindrical lenses.

[0070] In this example, three photodetectors (i.e., photodetector 101a (first photodetector), photodetector 101b (second photodetector), and photodetector 101c (third photodetector)) are provided as the photodetector 101, and three condensing lenses (i.e., condensing lens 102a (first condensing lens), condensing lens 102b (second condensing lens), and condensing lens 102c (third condensing lens)) are provided as the condensing lens 102. For example, the condensing lenses 102a to 102c and the photodetectors 101a to 101c are disposed near the center in the Y direction of the falling mirror 40, and are disposed in a row along the Z direction. Since the condensing lenses 102a to 102c and the photodetectors 101a to 101c only need to be able to detect light at multiple positions in the Z direction, they may be disposed outside the center in the Y direction of the falling mirror 40, or may be disposed in the Z direction, arranged obliquely.

[0071] The condensing lenses 102a to 102c respectively condense the corresponding beam groups of the laser light L4 transmitted through the falling mirror 40 onto the light receiving parts of the photodetectors 101a to 101c. The photodetectors 101a to 101c detect the intensities of the corresponding beam groups of the laser light L4 that have been condensed by the condensing lenses 102a to 102c. The light beams included in the beam groups are condensed by the condensing lenses, so that the light beams can be detected on a beam group basis.

[0072] In this example, the light beams B1 to B11 are grouped into three beam groups BG1 to BG3, and the four light beams B1 to B4 on the upper side (+Z side) are grouped into the beam group BG1 (first beam group), the three light beams B5 to B7 in the middle are grouped into the beam group BG2 (second beam group), and the four light beams B8 to B11 on the lower side (-Z side) are grouped into the beam group BG3 (third beam group). The light beams B1 to B4 of the beam group BG1 are converged by the condenser lens 102a, and the converged light is detected by the photodetector 101a. Similarly, the light beams B5 to B7 of the beam group BG2 are converged by the condenser lens 102b, and the converged light is detected by the photodetector 101b. The light beams B8 to B11 of the beam group BG3 are converged by the condenser lens 102c, and the converged light is detected by the photodetector 101c. A plurality of light beam groups can be detected simultaneously by a plurality of photodetectors.

[0073] As described above, in the pulse measuring instrument 100 according to the present embodiment, a plurality of light beams contained in the laser L4 are detected by a plurality of photodetectors 101a to 101c while grouping the light beams. By detecting the intensity of the laser L4 of each light beam (group) contained in the laser L4, it is possible to reliably detect the spatial variation of the laser L4. For example, the laser L4 is detected for each of the three light beam groups, which makes it possible to detect the spatial variation between the upper part, the center, and the lower part of the laser L4. The number of light beam groups to be detected is not limited to three, and may be any number of light beam groups, and the number of light beams included in each light beam group may be arbitrarily set. In addition, each light beam (the first light beam to the eleventh light beam) may be detected individually without providing any light beam group. By increasing the detection frequency using the photodetector, the detection accuracy of the spatial variation may be improved.

[0074] <Pulse waveform monitoring method of the first embodiment>

[0075] Will refer to Fig. 9 A pulse waveform monitoring method performed by the ELA apparatus 1 according to the present embodiment is described. Fig. 9 is a flowchart showing a pulse waveform monitoring method according to the present embodiment. For example, the pulse waveform monitoring method is performed separately from the manufacturing process of the semiconductor device in the ELA device 1. The manufacturing process of the semiconductor device is repeatedly performed for each group, wherein a plurality of semiconductor devices are grouped into one group. The pulse waveform monitoring method according to the present embodiment is performed by setting the ELA device 1 to a measurement mode between the manufacturing process of the previous group and the manufacturing process of the next group. As a result, the spatial variation of the laser light can be detected before the unevenness appears on the semiconductor film in the manufacturing process of the semiconductor device, so that the occurrence of unevenness on the semiconductor film can be suppressed in advance.

[0076] like Fig. 9 As shown, the ELA device 1 first starts irradiating laser light (S101). In other words, the control device 70 instructs the laser oscillator 10 to start oscillating in response to the user's operation. The laser oscillator 10 starts oscillating according to the instruction of the control device 70, and emits laser light L1. The emitted laser light L1 is shaped into a plurality of line beams by the beam shaper 30 via the input optical system 20. The shaped laser light L2 is reflected by the falling mirror 40, and the reflected laser light L3 is irradiated on the substrate 200. Since the pulse waveform monitoring method is performed separately from the manufacturing process of the semiconductor device, the substrate 200 may not be placed on the platform 51.

[0077] Subsequently, the ELA device 1 measures the laser light that has been started for irradiation (S102). In other words, the pulse measuring instrument 100 detects the intensity of the laser light L4 transmitted through the incident mirror 40. In this embodiment, the photodetectors 101a to 101c of the pulse measuring instrument 100 divide the light beams B1 to B11 of the laser light L4 into three light beam groups BG1 to BG3, detect the intensity of each light beam group, and output the detection results to the monitoring device 60.

[0078] Subsequently, the ELA device 1 generates a pulse waveform of the measured laser light (S103). In other words, the monitoring device 60 acquires the intensity of the beam groups BG1 to BG3 from the pulse measuring instrument 100, and generates a pulse waveform for each beam group BG1 to BG3 based on the acquired intensity. For example, the pulse width is set to 20ns to 100ns, and the pulse waveform is generated with a period of the pulse width.

[0079] Fig.10 An example of the generated pulse waveform is shown. Since the laser in this embodiment is an excimer laser, the laser has a waveform in which a first peak P1 and a second peak P2 appear continuously, and the second peak has an intensity lower than the intensity of the first peak P1 that appears first. The area A1 of the pulse waveform represents the energy of the pulse.

[0080] The monitoring device 60 calculates the first peak P1, the second peak P2 and the area A1 (energy) as evaluation parameters of the pulse. Note that other evaluation parameters such as pulse width and rise time to the first peak P1 may be calculated. In addition, the monitoring device 60 determines statistical values ​​of the evaluation parameters such as variance value (σ), average value, minimum value and maximum value based on the pulse waveform generated in a predetermined period.

[0081] Subsequently, the ELA device 1 determines whether there is a spatial variation in the pulse waveform (S104). In other words, the monitoring device 60 evaluates the spatial variation based on the pulse waveforms of the beam groups BG1 to BG3. The monitoring device 60 compares the pulse waveform of the beam group BG1, the pulse waveform of the beam group BG2, and the pulse waveform of the beam group BG3. For example, the monitoring device 60 determines the differences in the variance value, the average value, the minimum value, the maximum value, etc. of the first peak P1, the second peak P2, and the area A1, which are evaluation parameters of the pulse waveform. The difference in the evaluation parameters of the pulse waveform at a specific time can be determined. By obtaining the difference in variance values ​​and the like based on a plurality of pulse waveforms, the variation can be accurately evaluated. For example, in the case where the difference in the variance value of the evaluation parameter is greater than a predetermined threshold value, the monitoring device 60 determines that there is a spatial variation, and in the case where the difference is not greater than a predetermined threshold value, the monitoring device 60 determines that there is no spatial variation.

[0082] If it is determined in S104 that there is no spatial variation, the monitoring method is terminated and the ELA device 1 performs a manufacturing process on the next group of semiconductor devices. On the other hand, when it is determined that there is a spatial variation, the ELA device 1 adjusts the laser (S105). In other words, when the monitoring device 60 determines that there is a spatial variation, the control device 70 controls the angle of the resonant cavity mirror 12 of the laser oscillator 10 to adjust the intensity of the spatial distribution of the laser L1. The control device 70 changes the tilt of the resonant cavity mirror 12 by a predetermined angle and further measures the laser in S102 to S103. The adjustment of the laser is repeated until the difference in the evaluation value of the evaluation parameter converges and it is determined that there is no spatial variation. The angle for adjusting the resonant cavity mirror 12 can be changed according to the amplitude of the spatial variation, etc.

[0083] <Measurement Results>

[0084] See also Figures 11 to 13 , a measurement result in the case of using the pulse measurement instrument 900 of the comparative example and a measurement result in the case of using the pulse measurement instrument 100 according to the present embodiment are described. Figures 11 to 13 Measurement results at pulse repetition frequencies of 50 Hz, 300 Hz and 500 Hz are shown. Fig.11 The pulse waveform at each frequency is shown. Fig.12 shows the variance value (σ) of the first peak P1 of the pulse waveform, and Fig.13 The variance value (σ) of the area A1 (energy) of the pulse waveform is shown.

[0085] like Fig.11 As shown, the pulse waveform measured by the pulse measuring instrument 900 of the comparative example has a substantially ideal shape (e.g., Fig.10). The comparative example can only measure a stable pulse waveform, and therefore cannot grasp any spatial variation. On the other hand, the pulse waveform measured by the pulse measurement instrument 100 according to the present embodiment obviously has different shapes in the beam groups BG1 to BG3 at any frequency. Therefore, the present embodiment can grasp the spatial variation by comparing the waveforms of the beam groups BG1 to BG3.

[0086] exist Fig.11 In the example, at a frequency of 50 Hz, the pulse waveform of the beam group BG3 is close to the ideal pulse waveform as in the comparative example. Comparing the pulse waveforms of the beam groups BG1 to BG3, the pulse waveforms of the beam groups BG1 and BG2 have a first peak P1 and a second peak P2 that are lower than the first peak and the second peak of the pulse waveform of the beam group BG3, and the shape of the convex portion of the first peak P1 in the beam groups BG1 and BG2 is blunt.

[0087] In addition, at a frequency of 300 Hz, the pulse waveforms of the beam groups BG2 and BG3 are close to the ideal pulse waveform in the comparative example. Comparing the pulse waveforms of the beam groups BG1 to BG3, the pulse waveform of the beam group BG1 has a first peak P1 and a second peak P2, which are lower than the first peak and the second peak of the pulse waveforms of the beam groups BG2 and BG3, and the shape of the first peak P1 of the beam group BG1 is blunt.

[0088] In addition, at a frequency of 500 Hz, the pulse waveforms of the beam groups BG1 to BG3 are all different from the ideal pulse waveform. Comparing the pulse waveforms of the beam groups BG1 to BG3, the pulse waveforms of the beam groups BG1 and BG3 have first peaks P1 and second peaks P2 that are lower than the first peaks and second peaks of the pulse waveform of the beam group BG2. In addition, the shape of the convex portion of the first peak P1 in the pulse waveform of the beam group BG1 is blunter than the shape of the convex portion in the pulse waveforms of the beam groups BG2 and BG3.

[0089] like Fig.12 As shown, the variance value of the first peak P1 of the pulse waveform measured by the pulse measuring instrument 900 in the comparative example has a small change at a frequency of 50 Hz to 500 Hz. In the comparative example, since only the first peak P1 of the stable pulse waveform can be measured, it is impossible to grasp the spatial variation. On the other hand, in the measurement results by the pulse measuring instrument 100 according to the present embodiment, differences appear between the beam groups BG1 to BG3 at any frequency. Therefore, the spatial variation can be grasped by comparing the first peak P1 of the beam groups BG1 to BG3. In particular, at a frequency of 500 Hz, the difference between the beam group BG2 and the beam group BG3 is large, so that it can be determined that there is a spatial variation in the present embodiment.

[0090] exist Fig.12, at 50 Hz, the value of beam group B1 is equal to 1.1, the value of beam group B2 is equal to 0.9, and the value of beam group B3 is equal to 0.5. At 300 Hz, the value of beam group B1 is equal to 1.1, the value of beam group B2 is equal to 1.0, and the value of beam group B3 is equal to 0.6. In other words, at 50 Hz and 300 Hz, there is a difference of approximately 0.5 between each of beam group B1 and beam group B2 and beam group B3. In addition, at 500 Hz, the value of beam group B1 is equal to 2.9, the value of beam group B2 is equal to 1.5, and the value of beam group B3 is equal to 4.1. In other words, at 500 Hz, there is a difference of 1.4 between beam group B1 and beam group B2, and there is also a difference of 2.6 between beam group B2 and beam group B3, making the spatial variation large.

[0091] like Fig.13 As shown, the variance value of the area A1 of the pulse waveform measured by the pulse measuring instrument 900 of the comparative example has a small change in the frequency from 50 Hz to 500 Hz. In the comparative example, as in the case of the first peak P1, only the area A1 of the stable pulse waveform can be measured, so that it is impossible to grasp the spatial variation. On the other hand, the measurement results obtained by the pulse measuring instrument 100 according to the present embodiment show that differences occur between the beam groups BG1 to BG3 at any frequency. Therefore, the spatial variation can be grasped by comparing the areas A1 of the beam groups BG1 to BG3. As shown in Fig.12 As in the case of the first peak P1 shown, at a frequency of 500 Hz, the difference between the beam group BG2 and the beam group BG3 is large, so that it can be determined that there is a spatial variation in this embodiment.

[0092] exist Fig.13 , at 50 Hz, the value of beam group B1 is equal to 0.9, the value of beam group B2 is equal to 0.8, and the value of beam group B3 is equal to 0.4. In other words, at 50 Hz, there is a difference of about 0.5 between each of beam group B1 and beam group B2 and beam group B3. In addition, at 300 Hz, the value of beam group B1 is equal to 1.3, the value of beam group B2 is equal to 1.4, and the value of beam group B3 is equal to 0.6. In other words, at 300 Hz, there is a difference of about 0.8 between each of beam group B1 and beam group B2 and beam group B3. In addition, at 500 Hz, the value of beam group B1 is equal to 2.3, the value of beam group B2 is equal to 0.9, and the value of beam group B3 is equal to 7.0. In other words, at 500 Hz, there is a difference of 1.4 between beam group B1 and beam group B2, and there is also a difference of 6.1 between beam group B2 and beam group B3, making the spatial variation large.

[0093] <Effects of the First Embodiment>

[0094] As described above, in the present embodiment, the laser annealing apparatus is configured to monitor the spatial variation of the laser used to irradiate the object to be processed, and to control the laser according to the spatial variation. As a result, the laser that may be associated with the unevenness of the semiconductor film to be formed can be detected, and the occurrence of unevenness in the semiconductor film can be suppressed. In addition, the laser to be used for irradiation can be optimized according to the individual differences of the laser oscillator. In addition, in the pulse measuring instrument, the spatial variation can be reliably detected by detecting the intensity of each of the multiple beam groups (or multiple beams) included in the laser. For example, by providing multiple photodetectors, the intensity of multiple beam groups can be detected simultaneously.

[0095] (Second Embodiment)

[0096] Next, the second embodiment is described. In this embodiment, only the structure of the pulse measuring instrument equipped in the ELA device is different from that in the first embodiment. The pulse measuring instrument according to this embodiment measures the light beam selected by the slit portion through a photodetector. The rest is the same as in the first embodiment, so its description is omitted.

[0097] <Pulse Measurement Device of Second Embodiment>

[0098] Reference Figures 14 to 18 The configuration of the pulse measurement device 100 according to this embodiment will be described. Fig.14 is a side view showing a schematic structure of a pulse measuring instrument 100, Fig.15 is a perspective view showing a schematic structure of a pulse measuring instrument 100, Fig.16 FIG. 1 is a front view of the slit portion of the pulse measurement device 100 . Fig.17 and Fig.18 1 is a side view showing another state of the slit portion in the pulse measurement device 100 .

[0099] like Fig.14 and Fig.15 As shown in FIG. 1 , the pulse measuring instrument 100 according to the present embodiment includes a photodetector 101 and a condenser lens 102. The photodetector 101 and the condenser lens 102 have Figure 5 and Figure 6 In other words, the condensing lens 102 and the photodetector 101 are arranged near the center of the epi-mirror 40, the condensing lens 102 condenses the beam of the laser light L4, and the photodetector 101 detects the condensed beam.

[0100] In addition, the pulse measuring instrument 100 includes a slit portion 103 provided between the falling mirror 40 and the condensing lens 102. The slit portion 103 is a beam selection unit for selecting some beams of the laser light L4 and transmitting them. In other words, the condensing lens 102 condenses the beams of the laser light L4 selected by the slit portion 103.

[0101] like Fig.16 As shown, the slit portion 103 includes a rectangular shading plate 103a and a shading plate 103b arranged in parallel along the Y direction. The upper shading plate 103a shields the upper beam of the laser L4, and the lower shading plate 103b shields the lower beam of the laser L4, so that a part of the laser L4 passes through the opening portion 103c between the shading plate 103a and the shading plate 103b.

[0102] In addition, if Fig.14 As shown, the slit portion 103 is a movable slit portion that can be driven in the Z direction by the cylinder 104. For example, the cylinder 104 is a two-stage cylinder, and by driving the slit portion 103 to select any one of the beam groups BG1 to BG3, the slit portion 103 stops at the two-stage ( Fig.14 The cylinder 104 includes a driving unit 104a for driving the shading plate 103a and a driving unit 104b for driving the shading plate 103b. The shading plate 103a and the shading plate 103b are driven in coordination with each other by the driving unit 104a and the driving unit 104b to move the opening portion 103c up and down in the Z direction, thereby selecting the light beam in the laser L4 to be transmitted through the opening portion 103c. The driving unit 104b drives the upper end portion of the lower shading plate 103b from the position Z1 to the position Z2, and further drives it from the position Z2 to the position Z3. The driving unit 104a drives the lower end portion of the upper shading plate 103a from the position Z4 to the position Z3, and further drives it from the position Z3 to the position Z2. For example, the driving of the driving unit 104a and the driving unit 104b is controlled by the monitoring device 60.

[0103] Fig.14 , Fig.17 and Fig.18 Three states of the slit portion 103 are shown. Fig.14 The state is shown in which the slit portion 103 allows the light beam group BG3 including the lower four light beams B8 to B11 among the light beams B1 to B11 to pass through. In other words, the upper end of the lower light shielding plate 103b is positioned at the position Z1 (first position) by the driving unit 104b, and the lower end of the upper light shielding plate 103a is positioned at the position Z2 (second position) by the driving unit 104a, whereby the light beams B8 to B11 pass through the opening portion 103c between the position Z1 and the position Z2.

[0104] Fig.17 The state is shown in which the slit portion 103 allows the light beam group BG2 including the three center light beams B5 to B7 among the light beams B1 to B11 to pass through. In other words, the upper end portion of the lower light shielding plate 103b is positioned at the position Z2 (second position) by the driving unit 104b, and the lower end portion of the upper light shielding plate 103a is positioned at the position Z3 (third position) by the driving unit 104a, whereby the light beams B5 to B7 pass through the opening portion 103c between the position Z2 and the position Z3.

[0105] Fig.18 The state is shown in which the slit portion 103 allows the light beam group BG1 including the upper four light beams B1 to B4 of the light beams B1 to B11 to pass through. In other words, the upper end portion of the lower light shielding plate 103b is positioned at the position Z3 (third position) by the driving unit 104b, and the lower end portion of the upper light shielding plate 103a is positioned at the position Z4 (fourth position) by the driving unit 104a, whereby the light beams B1 to B4 pass through the opening portion 103c between the position Z3 and the position Z4.

[0106] The position of the opening portion 103c of the slit portion 103 may be set in advance, or may be automatically detected. For example, the position of one of the light shielding plate 103a and the light shielding plate 103b is fixed, and the intensity of the transmitted light is detected while gradually moving the position of the other light shielding plate in the Z direction. In this case, the accumulated value of the light intensity changes stepwise according to the light beam, so that the position of the selected light beam in the Z direction can be detected from the position where the light intensity changes greatly.

[0107] <Variant Pulse Measuring Instrument>

[0108] In the present embodiment, the light beam obtained by dividing the laser light may be detected by the photodetector as in the case of the first embodiment, or the undivided (or before division) laser light passing through the slit portion may be detected. Fig.19 FIG. 1 shows the structure of a pulse measuring instrument 100 of a variant for measuring undivided laser light (original beam). Fig.19 As shown, the pulse measuring instrument 100 of the variant has Fig.14 The pulse measuring device 100 of the illustrated embodiment has the same structure.

[0109] In this example, the undivided laser light L5 is reflected by the epi-mirror 40 to obtain the laser light L6, and a part of the light is transmitted through to obtain the laser light L7. Fig.14 As in the case shown, the slit portion 103 selects a portion of the laser light L7 and transmits it, the focusing lens 102 converges the portion of the laser light L7 selected by the slit portion 103, and the photodetector 101 detects the converged light.

[0110] <Effects of the Second Embodiment>

[0111] As described above, in the present embodiment, the pulse measuring instrument of the ELA device includes a slit portion for selecting the light to be measured. As a result, as in the first embodiment, the spatial variation of the laser light can be monitored. For example, by using a movable slit portion, the light to be measured can be arbitrarily selected, so that the light in multiple spaces can be detected by one detector. Even when the number of photodetectors provided is limited, the spatial variation of the laser light can be reliably monitored.

[0112] (Third Embodiment)

[0113] Next, the third embodiment is described. In this embodiment, only the structure of the pulse measuring instrument equipped in the ELA device is different from the structure in the first embodiment and the second embodiment. The pulse measuring instrument according to this embodiment measures the light beam selected by the slit portion through a plurality of photodetectors. The rest is the same as in the first embodiment and the second embodiment, so the description thereof is omitted.

[0114] <Pulse Measurement Device of the Third Embodiment>

[0115] Reference Figure 20 to Figure 22 The structure of the pulse measurement instrument 100 according to the present embodiment will be described. Fig. 20 is a side view showing a schematic structure of a pulse measuring instrument 100, Fig.21 is a perspective view showing a schematic structure of a pulse measuring instrument 100, Fig. 22 FIG. 1 is a front view of a slit portion in the pulse measurement device 100 .

[0116] like Fig. 20 and Fig.21 As shown, the pulse measuring instrument 100 according to the present embodiment includes a plurality of photodetectors 101 and a plurality of condensing lenses 102. The pulse measuring instrument 100 includes, for example, three photodetectors 101a to 101c and three condensing lenses 102a to 102c, as in the first embodiment. Figure 7 and Figure 8 In other words, the light beams B1 to B4 of the light beam group BG1 are detected by the photodetector 101a through the condenser lens 102a. Similarly, the light beams B5 to B7 of the light beam group BG2 are detected by the photodetector 101b through the condenser lens 102b, and the light beams B8 to B11 of the light beam group BG3 are detected by the photodetector 101c through the condenser lens 102c.

[0117] Furthermore, the pulse measuring instrument 100 includes the slit portion 103 provided between the incident mirror 40 and the condenser lens 102 as in the second embodiment. Fig. 22 As shown, the slit portion 103 is a rectangular shading plate 103d, and the shading plate 103d has rectangular opening portions 103e to 103g. The opening portions 103e to 103g are formed to be arranged obliquely in the Z direction in a manner corresponding to the position of the light beam of the transmitted laser L4. The corresponding light beams passing through the opening portions 103e to 103g are respectively converged by the condenser lenses 102a to 102c. The photodetectors 101a to 101c are respectively arranged at positions facing the opening portions 103e to 103g. For example, the opening portions 103e to 103g are formed at such positions that the opening portions 103e to 103g do not overlap with each other in the Z direction in the shading plate 103d, thereby any light beam can be selected and made to pass through each opening. In this example, when viewed from the incident surface side of the light shielding plate 103d, the opening portion 103e is formed on the upper left side in the light shielding plate 103d, and transmits the light beam group BG1 including the light beams B1 to B4. When viewed from the incident surface side of the light shielding plate 103d, the opening portion 103f is formed at the center of the light shielding plate 103d, and transmits the light beam group BG2 including the light beams B5 to B7. When viewed from the incident surface side of the light shielding plate 103d, the opening portion 103g is formed on the lower right side in the light shielding plate 103d, and transmits the light beam group BG3 including the light beams B8 to B11. The opening portion 103e may be formed on the upper right side in the light shielding plate 103d, the opening portion 103f may be formed in the center of the light shielding plate 103d, and the opening portion 103g may be formed on the lower left side in the light shielding plate 103d.

[0118] <Effects of the Third Embodiment>

[0119] As described above, in the present embodiment, as in the case of the second embodiment, the pulse measuring instrument of the ELA device includes a slit portion for selecting the light to be measured. As a result, the spatial variation of the laser light can be monitored as in the first and second embodiments. For example, the fixed slit portion is provided with opening portions corresponding to a plurality of lights to be measured, respectively, thereby making it possible to detect light in a plurality of spaces without providing any driving mechanism for driving the slit portion. In addition, by providing a plurality of photodetectors as in the first embodiment, a plurality of lights of the laser light can be detected simultaneously. The pulse measuring instrument in the present embodiment can also measure undivided laser light, as in the variant. Fig.19 shown.

[0120] (Another embodiment)

[0121] Next, as another embodiment, a method for manufacturing a semiconductor device by using the ELA apparatus according to the above-mentioned embodiment will be described. In the following method for manufacturing a semiconductor device, an annealing process is performed using the ELA apparatus according to the first to third embodiments in the step of crystallizing an amorphous semiconductor film.

[0122] The semiconductor device is a semiconductor device including a TFT (Thin Film Transistor), and in this case, an amorphous silicon film can be irradiated with laser light to crystallize the amorphous silicon film to form a polycrystalline silicon film. The polycrystalline silicon film is used as a semiconductor layer having a source region, a channel region, and a drain region of the TFT.

[0123] <Method for Manufacturing Semiconductor Device According to Another Embodiment>

[0124] Figure 23 to Figure 27 is a cross-sectional view showing an example of a method for manufacturing a semiconductor device. The ELA device according to the above-described embodiment is suitable for manufacturing a TFT array substrate. Hereinafter, a method for manufacturing a semiconductor device having a TFT will be described.

[0125] First, if Fig.23 As shown in FIG. 1 , a gate electrode 92 is formed on a glass substrate 91 (corresponding to the substrate 200 described above). For example, a metal thin film including aluminum or the like can be used as the gate electrode 92. Next, as shown in FIG. Fig.24 As shown in FIG. 1 , a gate insulating film 93 is formed on the gate electrode 92. The gate insulating film 93 is formed to cover the gate electrode 92. Thereafter, as shown in FIG. Fig.25 As shown, an amorphous silicon film 94 (corresponding to the above-mentioned amorphous silicon film 201a) is formed on the gate insulating film 93. The amorphous silicon film 94 is provided so as to overlap with the gate electrode 92 via the gate insulating film 93.

[0126] The gate insulating film 93 is a silicon nitride film (SiN X ), silicon oxide film (SiO2 film), a laminated film thereof, etc. Specifically, a gate insulating film 93 and an amorphous silicon film 94 are continuously formed by a CVD (Chemical Vapor Deposition) method. The glass substrate 91 is used as a semiconductor film in a laser processing device through the amorphous silicon film 94.

[0127] Afterwards, if Fig.26 As shown, the amorphous silicon film 94 is irradiated with laser light L3 using the above-mentioned ELA apparatus to crystallize the amorphous silicon film 94, thereby forming a polycrystalline silicon film 95 (corresponding to the above-mentioned polycrystalline silicon film 201b). As a result, the polycrystalline silicon film 95 in which silicon has been crystallized is formed on the gate insulating film 93. Prior to this step, a pulse waveform monitoring method using the above-mentioned ELA apparatus is performed, so that the occurrence of unevenness in the polycrystalline silicon film 95 can be suppressed.

[0128] Afterwards, if Fig. 27 As shown, an interlayer insulating film 96, a source electrode 97a, and a drain electrode 97b are formed on the polysilicon film 95. The interlayer insulating film 96, the source electrode 97a, and the drain electrode 97b can be formed by using a general photolithography method or a film forming method. The subsequent manufacturing steps are omitted because they are different depending on the device to be manufactured in the end.

[0129] By using the above method for manufacturing a semiconductor device, a semiconductor device having a TFT including a polycrystalline semiconductor film can be manufactured. Such a semiconductor device is suitable for controlling a high-definition display such as an organic electroluminescent display (organic light emitting diode display). By suppressing the unevenness of the polycrystalline silicon film as described above, a display device having excellent display characteristics can be manufactured with high productivity.

[0130] The present invention is not limited to the above-mentioned embodiments, and can be modified appropriately without departing from the gist of the present invention. For example, in the laser annealing apparatus, the present invention is not limited to the example of irradiating an amorphous silicon film with a laser beam to form a polycrystalline silicon film, but can also irradiate an amorphous silicon film with laser to form a microcrystalline silicon film. In addition, an amorphous film other than a silicon film can be irradiated with laser to form a crystalline film.

[0131] This application claims priority based on Japanese patent application JP 2019-165811 filed on September 12, 2019, and incorporates all the disclosure contents thereof herein.

[0132] Reference numerals list

[0133] 1 ELA device

[0134] 2 Annealing optical system

[0135] 10 Laser Oscillator

[0136] 11, 12 Resonant cavity mirror

[0137] 20 Input Optical System

[0138] 21, 22 Reflector

[0139] 30 Beam Shaper

[0140] 40. Falling mirror

[0141] 50 Laser irradiation chamber

[0142] 51 Platform

[0143] 52 Base

[0144] 60 Monitoring device

[0145] 70 Control device

[0146] 91 Glass substrate

[0147] 92 gate electrode

[0148] 93 Gate insulating film

[0149] 94 Amorphous silicon film

[0150] 95 Polysilicon film

[0151] 96 interlayer insulation film

[0152] 97a Source electrode

[0153] 97b Drain electrode

[0154] 100 Pulse measuring instrument

[0155] 101, 101a, 101b, 101c Photodetector

[0156] 102, 102a, 102b, 102c Condenser lens

[0157] 103 Seam

[0158] 103a, 103b, 103d Sunshade

[0159] 103c, 103e, 103f, 103g opening

[0160] 104 Cylinder

[0161] 104a, 104b drive unit

[0162] 200 Base Material

[0163] 201 Silicone membrane

[0164] 201a Amorphous silicon film

[0165] 201b Polysilicon film

Claims

1. A laser processing device, comprising: a laser generating device configured to generate laser light to be applied to an object to be treated; a photodetection device configured to detect a first portion of light and a second portion of light contained in the laser light; as well as a monitoring unit configured to compare a detection result of the first portion of light with a detection result of the second portion of light, wherein the laser is a line beam for irradiating a substrate and crystallizing an amorphous film on the substrate to form a crystalline film, and includes a line beam extending in a direction perpendicular to the irradiation direction, wherein the first portion of light and the second portion of light include a first portion and a second portion of light arranged along a short axis direction in a cross section of the line light beam, wherein the photoelectric detection device comprises a first photodetector configured to detect the first portion of light and a second photodetector configured to detect the second portion of light, The monitoring unit compares waveforms of a first portion of light detected by the first photodetector and a second portion of light detected by the second photodetector.

2. The laser processing device according to claim 1, characterized in that: The laser is a gas laser.

3. The laser processing device according to claim 2, characterized in that: The laser is an excimer laser.

4. The laser processing device according to claim 1 or 2, characterized in that: Also included is an optical system configured to split the laser light into a plurality of split beams, The photoelectric detection device detects a first split light beam and a second split light beam included in the plurality of split light beams as the first partial light and the second partial light.

5. The laser processing device according to claim 4, characterized in that: The photodetection device detects a first divided light beam group and a second divided light beam group included in the plurality of divided light beams as the first partial light and the second partial light.

6. The laser processing device according to claim 1, characterized in that: The photoelectric detection device comprises: a first condenser lens configured to condense the first portion of light to a first photodetector; and A second condenser lens is configured to condense the second portion of light onto a second photodetector.

7. The laser processing device according to claim 1, characterized in that: The photodetection device further includes a slit portion configured to allow the first portion of light and the second portion of light to pass through.

8. The laser processing device according to claim 1, characterized in that: The monitoring unit determines a difference in an evaluation parameter between the waveforms.

9. The laser processing device according to claim 8, characterized in that: The evaluation parameter includes the peak value or energy of the waveform.

10. The laser processing device according to claim 8, characterized in that: The monitoring unit determines a difference between statistical values ​​of evaluation parameters of the waveform.

11. The laser processing device according to claim 10, characterized in that: Each of the statistical values ​​includes a variance value, an average value, a minimum value or a maximum value.

12. The laser processing device according to claim 1 or 2, characterized in that: A control unit is also included, the control unit being configured to control a condition for generating the laser in the laser generating device based on a result of the comparison.

13. The laser processing device according to claim 12, characterized in that: The control unit controls the angle of the resonant cavity reflector provided in the laser generating device.

14. A laser monitoring method comprising the following steps: (A) generating laser light to be applied to an object to be treated; (B) detecting a first portion of light and a second portion of light contained in the laser light; as well as (C) comparing the detection result of the first portion of light with the detection result of the second portion of light, wherein the laser is a line beam for irradiating a substrate and crystallizing an amorphous film on the substrate to form a crystalline film, and includes a line beam extending in a direction perpendicular to the irradiation direction, wherein the first portion of light and the second portion of light include a first portion and a second portion of light arranged along a short axis direction in a cross section of the line light beam, wherein, in (B), the first portion of light is detected by a first photodetector, and the second portion of light is detected by a second photodetector, Wherein, in (C), the waveform of the first portion of light detected by the first photodetector and the waveform of the second portion of light detected by the second photodetector are compared.

15. The laser monitoring method according to claim 14, characterized in that: The method further includes a step (D) of controlling conditions for generating the laser light based on the comparison result.

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