Laser annealing equipment, laser annealing method, and method for manufacturing semiconductor device

Abstract

To provide laser annealing equipment, a laser annealing method, and a manufacturing method that can stably perform the annealing process.SOLUTION: Laser annealing equipment according to the embodiment comprises: a laser light source 11 that emits laser beam L1; an annealing optical system 10 that irradiates laser beam L1 onto a semiconductor film; a probe light source 21 that emits probe light L2; an optical system that irradiates probe light L2 onto the semiconductor film after the laser light L1 has been irradiated; a photodetector 25 that detects the transmitted light of the probe light transmitted through the substrate 100 or the reflected light of the probe light reflected by the substrate; a transport path for transporting the substrate 100 so as to change the irradiation position with respect to the substrate 100; and a processing section that sets the process conditions for laser annealing based on the detection results by the photodetector when the substrate is transported.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a laser annealing apparatus, a laser annealing method, and a method for manufacturing a semiconductor device. [Background technology]

[0002] Patent Document 1 discloses a laser irradiation device that irradiates a substrate with a line-shaped laser beam. This laser irradiation device includes a levitation unit that levitates the substrate, a holding mechanism that adsorbs and holds the substrate on the levitation unit, and a moving mechanism that moves the holding mechanism in the transport direction. When viewed from above, a moving mechanism is provided on each end side of the rectangular levitation unit. The four moving mechanisms transport the substrate in a circular manner. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6887234 Summary of the Invention [Problem to be solved by the invention]

[0004] In such a laser annealing apparatus, it is desirable to perform the laser annealing process stably.

[0005] Other objects and novel features will become apparent from the description of this specification and the accompanying drawings. [Means for solving the problem]

[0006] According to one embodiment, a laser annealing apparatus includes a laser light source that emits laser light for crystallizing an amorphous semiconductor film formed on a substrate, an annealing optical system that irradiates the semiconductor film with the laser light, a probe light source that emits probe light, an optical system that irradiates the semiconductor film with the probe light after the laser light has been irradiated, a photodetector that detects transmitted light of the probe light that has passed through the substrate or reflected light of the probe light that has been reflected by the substrate, a transport path that transports the substrate so as to change the irradiation position of the laser light and the probe light relative to the substrate, and a processing unit that sets process conditions for laser annealing based on a detection result of the photodetector when the substrate is transported.

[0007] According to one embodiment, a laser annealing method includes the steps of: (A) irradiating a laser beam onto an amorphous semiconductor film formed on a substrate to crystallize the semiconductor film; (B) irradiating a probe beam onto the semiconductor film after the laser beam has been irradiated; (C) detecting a transmitted light of the probe beam that has passed through the substrate or a reflected light of the probe beam that has been reflected by the substrate with a photodetector; (D) transporting the substrate to change the irradiation positions of the laser beam and the probe beam on the substrate; (E) setting process conditions for laser annealing based on a detection result of the photodetector when the substrate is transported; and (F) performing laser annealing by irradiating the substrate with the laser beam under the process conditions to crystallize the semiconductor film.

[0008] According to one embodiment, a method for manufacturing a semiconductor device includes the steps of (S1) setting process conditions for laser annealing, (S2) forming an amorphous semiconductor film on a substrate, and (S3) irradiating the semiconductor film with laser light under the process conditions to crystallize the semiconductor film, thereby performing laser annealing. The step of (S1) setting process conditions includes the steps of (a) irradiating the semiconductor film formed on the substrate with laser light to crystallize the semiconductor film, (b) irradiating the semiconductor film after the laser light is irradiated with probe light, (c) detecting with a photodetector a transmitted light of the probe light that has passed through the substrate or a reflected light of the probe light that has been reflected by the substrate, (d) transporting the substrate to change the irradiation positions of the laser light and the probe light relative to the substrate, and (e) setting process conditions for laser annealing based on a detection result of the photodetector when the substrate is transported.

[0009] According to one embodiment, a laser annealing apparatus includes a laser light source that emits laser light for crystallizing an amorphous semiconductor film formed on a substrate, an annealing optical system that irradiates the semiconductor film with the laser light, a probe light source that emits probe light, an optical system that irradiates the semiconductor film with the probe light after the laser light is irradiated, a photodetector that detects transmitted light of the probe light that has passed through the substrate or reflected light of the probe light that has been reflected by the substrate, a transport path that transports the substrate so as to change the irradiation position of the laser light and the probe light relative to the substrate, a beam sampler that extracts a portion of the laser light, a laser light detector that detects the laser light extracted by the beam sampler, and a processing unit that sets process conditions for laser annealing based on detection results of the photodetector and the laser light detector when the substrate is transported.

[0010] According to one embodiment, a laser annealing method includes: (STA) a step of irradiating a laser beam onto an amorphous semiconductor film formed on a substrate so as to crystallize the semiconductor film; (STB) a step of irradiating a probe beam onto the semiconductor film after the laser beam has been irradiated; (STC) a step of detecting a transmitted beam of the probe beam that has passed through the substrate or a reflected beam of the probe beam that has been reflected by the substrate with a photodetector; (STD) a step of extracting a portion of the laser beam by a beam sampler disposed in a light path of the laser beam; (STE) a step of detecting the laser beam extracted by the beam sampler with a laser beam detector; (STF) a step of transporting the substrate so as to change the irradiation positions of the laser beam and the probe beam with respect to the substrate; (STG) a step of setting process conditions for laser annealing based on detection results by the photodetector and the laser beam detector when the substrate is transported; and (STH) a step of performing laser annealing in which the laser beam is irradiated onto the substrate under the process conditions to crystallize the semiconductor film.

[0011] According to one embodiment, a method for manufacturing a semiconductor device includes the steps of (S1) setting process conditions for laser annealing, (S2) forming an amorphous semiconductor film on a substrate, and (S3) performing laser annealing by irradiating the semiconductor film with laser light under the process conditions so as to crystallize the semiconductor film, wherein the step of (S1) setting process conditions includes the steps of (sta) irradiating the semiconductor film formed on the substrate with laser light so as to crystallize the semiconductor film, (stb) irradiating the semiconductor film with probe light after the laser light irradiation, and (stc) detecting the amount of the probe light transmitted through the substrate. The method includes the steps of detecting transmitted light or reflected light of the probe light reflected by the substrate using a photodetector, (std) extracting a portion of the laser light using a beam sampler arranged in the optical path of the laser light, (ste) detecting the laser light extracted by the beam sampler using a laser light detector, (stf) transporting the substrate so as to change the irradiation position of the laser light and the probe light relative to the substrate, and (stg) setting process conditions for laser annealing based on the detection results of the photodetector and the laser light detector when the substrate is transported. Effect of the Invention

[0012] According to the embodiment, it is possible to provide a laser annealing apparatus, a laser annealing method, and a method for manufacturing a semiconductor device that can perform a stable annealing process. [Brief description of the drawings]

[0013] [Figure 1] FIG. 2 is a side view showing the configuration of a laser annealing apparatus. [Diagram 2] FIG. 2 is a side view showing the configuration of a laser annealing apparatus. [Diagram 3] FIG. 2 is a schematic diagram for explaining a laser light and a probe light on a substrate. [Figure 4] FIG. 11 is a side view showing the configuration of a laser annealing apparatus according to a second embodiment. [Diagram 5]FIG. 11 is a side view showing the configuration of a laser annealing apparatus according to a third embodiment. [Figure 6] 1 is a graph showing the detected light amounts of laser light L1 and probe light L3. [Figure 7] FIG. 13 is a side view showing the configuration of a laser annealing apparatus according to a fourth embodiment. [Figure 8] 4 is a flowchart showing a method for adjusting a pulse waveform in a laser annealing apparatus. [Figure 9] FIG. 2 is a schematic diagram showing an example of a configuration for adjusting a pulse waveform. [Figure 10] FIG. 2 is a schematic diagram showing an example of a configuration for adjusting a pulse waveform. [Figure 11] 1 is a cross-sectional view showing a simplified configuration of an organic EL display. [Figure 12] 1A to 1C are cross-sectional views showing steps of a manufacturing method of a semiconductor device according to an embodiment of the present invention. [Figure 13] 1A to 1C are cross-sectional views showing steps of a manufacturing method of a semiconductor device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] First embodiment The laser annealing apparatus according to the present embodiment is, for example, an excimer laser annealing (ELA) apparatus for forming a low temperature polysilicon (LTPS) film. Hereinafter, the laser annealing apparatus, the inspection method for a semiconductor device, and the manufacturing method according to the present embodiment will be described with reference to the drawings.

[0015] The configuration of an ELA apparatus 1 according to the present embodiment will be described with reference to Figures 1 and 2. Figure 1 is a side view that shows a schematic view of the ELA apparatus 1. Figure 2 is an XY plan view that shows a schematic view of the configuration of the ELA apparatus 1.

[0016] 1, the ELA apparatus 1 irradiates a laser beam L1 onto a silicon film 101 formed on a substrate 100. This makes it possible to convert the amorphous silicon film (amorphous silicon film: a-Si film) 101 into a polycrystalline silicon film (polysilicon film: p-Si film) 101. The substrate 100 is, for example, a transparent substrate such as a glass substrate.

[0017] 1 and 2, an XYZ three-dimensional orthogonal coordinate system is shown for the sake of clarity. The Z direction is the vertical direction, which is perpendicular to the substrate 100. The XY plane is a plane parallel to the surface of the substrate 100 on which the silicon film 101 is formed. The X direction is the short side direction of the rectangular substrate 100, and the Y direction is the long side direction of the substrate 100.

[0018] In the ELA apparatus 1, the laser light L1 is a line beam with the Y direction as the longitudinal direction. The silicon film 101 is irradiated with the laser light L1 while the substrate 100 is transported in the +X direction by a linear motor or the like. In FIG. 1, the silicon film 101 before irradiation with the laser light L1 is shown as an amorphous silicon film 101a, and the silicon film 101 after irradiation with the laser light L1 is shown as a polysilicon film 101b.

[0019] The ELA device 1 includes an annealing optical system 10, an illumination optical system 20, a detection optical system 30, a levitation unit 43, a holding mechanism 44, and a chamber 50. The annealing optical system 10 is an optical system for irradiating the silicon film 101 with laser light L1 for crystallizing the amorphous silicon film 101a. The illumination optical system 20 and the detection optical system 30 are optical systems for evaluating the variation in the crystal state of the substrate 100. Specifically, the process conditions of the annealing process are determined based on the detection result of the probe light L3.

[0020] The optical system of the ELA device 1 includes a laser light source 11, a mirror 12, a projection lens 13, a probe light source 21, a mirror 22, a condenser lens 24, a photodetector 25, a processing device 26, a filter 27, etc. In addition, the projection lens 13 is omitted in FIG.

[0021] The substrate 100 is placed on the levitation unit 43. The levitation unit 43 ejects gas for levitating the substrate 100. As the levitation unit 43 ejects gas upward, the substrate 100 is levitated above the levitation unit 43. In other words, an air gap (not shown in FIG. 1) is provided between the substrate 100 and the levitation unit 43.

[0022] Furthermore, a holding mechanism 44 is provided to hold the substrate 100. The holding mechanism 44 and the floating unit 43 form a transport path along which the substrate 100 is transported. The holding mechanism 44 is disposed outside the floating unit 43 so as to hold the end of the substrate 100 on the -Y side. The holding mechanism 44 vacuum-adsorbs the end of the substrate 100. The holding mechanism 44, which holds the substrate 100, moves in the X direction by a moving mechanism (not shown). As a result, the substrate 100 is transported in the X direction, and the irradiation position of the laser light L1 on the substrate 100 changes. As the substrate 100 passes through the linear irradiation region P1, the laser light is irradiated onto approximately half of the substrate 100. Then, by rotating the substrate 100 180° around the Z axis and transporting it in the same manner, the laser light L1 can be irradiated onto approximately the entire surface of the substrate 100.

[0023] The chamber 50 houses the levitation unit 43 and an optical system. For example, the chamber 50 contains the levitation unit 43, the holding mechanism 44, the condenser lens 24, the filter 27, the photodetector 25, and the like. The chamber 50 also includes a window 51 through which the laser light L1 and the probe light L2 pass. Thus, the laser light L1 and the probe light L2 that pass through the window 51 are incident on the substrate 100.

[0024] The annealing optical system 10 for irradiating the silicon film 101 with the laser light L1 will be described. The annealing optical system 10 is disposed above (on the +Z side of) the substrate 100. The laser light source 11 is, for example, an excimer laser light source that emits an excimer laser light with a central wavelength of 308 nm. The laser light source 11 also emits pulsed laser light L1. The laser light source 11 emits the laser light L1 toward a mirror 19. The laser light L1 reflected by the mirror 19 enters the shaping optical system 60. The shaping optical system 60 shapes the laser light L1.

[0025] The shaping optical system 60 may shape the laser light L1 so as to change the spatial distribution of the laser light L1 in a plane perpendicular to the optical axis. For example, the shaping optical system 60 may shape the laser light L1 so as to form a line beam on the substrate 100, and may further shape the laser light L1 so that the line beam has a flat-top distribution on the substrate 100.

[0026] Furthermore, the shaping optical system 60 can adjust the pulse waveform of the laser light L1. For example, the shaping optical system 60 has a branching beam splitter, a combining beam splitter, and a mirror. Two beams branched by the branching beam splitter are reflected by a plurality of mirrors. Then, the two beams reflected by the mirrors are combined by the combining beam splitter. By changing the distance between the mirrors in at least one of the beam paths, the optical path length of the beam changes. This allows the pulse waveform to be adjusted so that the laser light L1 has a desired pulse length.

[0027] The laser light L1 shaped by the shaping optical system 60 is incident on the mirror 12. The mirror 12 and the projection lens 13 are disposed directly above the substrate 100. The mirror 12 is, for example, a dichroic mirror that selectively transmits light according to the wavelength. The mirror 12 has wavelength characteristics that transmit light with the wavelength of the probe light L2 and reflect light with the wavelength of the laser light L1. Therefore, the mirror 12 reflects the laser light L1. The laser light L1 reflected by the mirror 12 travels in an oblique direction between the -Z direction and the -X direction.

[0028] The laser light L1 is reflected by the mirror 12 and enters the projection lens 13. The projection lens 13 has a plurality of lenses for projecting the laser light L1 onto the substrate 100, i.e., onto the silicon film 101. The laser light L1 from the projection lens 13 enters the substrate 100 via the window 51.

[0029] The projection lens 13 focuses the laser light L1 on the substrate 100. Here, referring to FIG. 3, the shape of the irradiation area P1 of the laser light L1 on the substrate 100 (silicon film 101) and its spatial distribution will be described. On the substrate 100, the laser light L1 forms a linear irradiation area P1 along the Y direction. That is, on the substrate 100, the laser light L1 is a line beam with the Y direction as the longitudinal direction and the X direction as the transverse direction. The laser light L1 is irradiated onto the silicon film 101 while the substrate 100 is transported in the +X direction. This allows the laser light L1 to be irradiated onto a belt-shaped area with a width equal to the length of the irradiation area P1 in the Y direction. In addition, the transport direction does not have to be the orthogonal X direction as long as it is inclined from the longitudinal direction of the line beam.

[0030] For example, the size of the irradiation area P1 in the X direction can be 750 mm or more. The size of the irradiation area P1 in the Y direction can be 400 μm or less. In addition, the laser light L1 has a top-flat distribution in the X direction and the Y direction. Of course, the laser light L1 may have a Gaussian distribution in at least one of the X direction and the Y direction.

[0031] Next, the illumination optical system 20 for irradiating the probe light L2 onto the substrate 100 will be described. The illumination optical system 20 is disposed on the upper side (+Z side) of the substrate 100. The probe light source 21 emits the probe light L2 having a wavelength different from that of the laser light L1. For example, a continuous wave (CW) semiconductor laser light source or the like can be used as the probe light source 21. The central wavelength of the probe light L2 is, for example, 401 nm. The wavelength of the probe light L2 is preferably a wavelength that is low in absorptance in the silicon film 101. For this reason, it is preferable to use a laser light source or an LED (Light Emitting Diode) light source that emits monochromatic light as the probe light source 21.

[0032] The probe light source 21 emits the probe light L2 toward the mirror 22. The mirror 22 reflects the probe light L2 toward the mirror 12. The mirror 12 is a dichroic mirror, and therefore transmits the probe light L2. Here, the optical axes of the probe light L2 and the laser light L1 coincide with each other. For example, the optical axes of the laser light L1 and the probe light L2 coincide with the optical axis of the projection lens 13.

[0033] The probe light L2 transmitted through the mirror 12 is incident on the projection lens 13. The probe light L2 from the projection lens 13 is incident on the substrate 100 through the window 51. The projection lens 13 focuses the probe light L2 on the silicon film 101.

[0034] As shown in Fig. 3, the projection lens 13 focuses the probe light L2 so that the probe light L2 becomes a minute spot. In the silicon film 101, the probe light L2 is incident on an irradiation area P1. That is, in the XY plane, the irradiation spot of the probe light L2 overlaps with the irradiation area P1. On the silicon film 101, a spot of the probe light L2 is formed near the center of the laser light L1 in the Y direction. For example, the spot diameter of the probe light L2 is about 300 µm.

[0035] The irradiation position of the probe light L2 on the silicon film 101 may be in the irradiation region P1 of the laser light L1 or in its vicinity. For example, as shown by the dashed line in FIG. 3, the probe light L2 may be irradiated near the end of the irradiation region P1 in the Y direction. The irradiation position of the probe light L2 may be included in the irradiation region P1. The irradiation position of the probe light L2 is not limited to a position overlapping with the irradiation region P1, and may be shifted from the irradiation region P1. For example, the irradiation position of the probe light L2 may be shifted in the +X direction from the irradiation region P1 of the laser light L1. In this case, the probe light L2 is incident on the silicon film 101 immediately after the laser light L1 is irradiated on the silicon film 101. Therefore, the probe light L2 is incident on the silicon film 101 in a state in which the silicon film 101 is melted by the laser light L1.

[0036] Furthermore, the probe light L2 may be irradiated to a plurality of points on the silicon film 101. For example, the probe light L2 may be irradiated to three points, namely, the center of the irradiation region P1 in the Y direction and near both ends. When irradiating the silicon film 101 with a plurality of probe lights L2, a plurality of probe light sources 21 may be used. Alternatively, the probe light L2 from one probe light source 21 may be split by a beam splitter or the like to form a plurality of beams.

[0037] At least a part of the probe light L2 is transmitted through the silicon film 101. Of the probe light L2, the transmitted light that is transmitted through the silicon film 101 is referred to as probe light L3. The levitation unit 43 is provided with an opening 43a through which the probe light L3 passes. The probe light L3 propagates through the detection optical system 30 after passing through the opening 43a.

[0038] The detection optical system 30 arranged below the substrate 100 will be described. The detection optical system 30 includes a condenser lens 24 and a filter 27. The condenser lens 24 and the filter 27 are arranged below the floating unit 43.

[0039] The probe light L3 that has passed through the opening 43a enters the condenser lens 24. The condenser lens 24 condenses the probe light L3 on the light receiving surface of the photodetector 25. The photodetector 25 is, for example, a photodiode, and detects the probe light L3. Furthermore, a filter 27 is disposed between the condenser lens 24 and the photodetector 25. The filter 27 is a wavelength filter that transmits light of the wavelength of the probe light L3 and cuts the wavelength of the laser light L1. This makes it possible to prevent the laser light L1 that has been diffused by the levitation unit 43, the chamber 50, etc. from entering the photodetector 25. For example, the filter 27 is a bandpass filter, a longpass filter, etc.

[0040] The photodetector 25 outputs a detection signal corresponding to the detected light amount of the probe light L3 to the processing device 26. The processing device 26 is a computer having a memory, a processor, etc. The detection value of the detection signal corresponds to the transmittance of the silicon film 101. Since the substrate 100 is transported in the +X direction at a constant speed, the photodetector 25 detects the profile of the detected light amount in the X direction (i.e., the transmittance of the silicon film 101).

[0041] The processing device 26 is a computing device that performs a predetermined calculation on the detection value of the detection signal. The processing device 26 may include an A / D converter that performs A / D conversion of the analog detection signal to a digital detection value. Alternatively, the photodetector 25 may include an A / D converter that performs A / D conversion of the analog detection signal to a digital detection value.

[0042] While scanning the substrate 100 in the +X direction, the photodetector 25 detects the probe light L3. Therefore, the processing device 26 acquires a plurality of detection values ​​according to the sampling rate of the photodetector 25 or the A / D converter. The processing device 26 has a memory for storing the plurality of detection values. Since the substrate 100 is scanned at a constant speed in the +X direction, the plurality of detection values ​​indicate a profile of the transmittance in the X direction.

[0043] Here, the transmittance of the silicon film 101 changes depending on the melting state of the silicon. Specifically, when the silicon melts, the reflectance increases and the transmittance decreases. When the silicon is not sufficiently melted, the amount of transmitted light of the probe light L3 decreases. The amount of light detected by the photodetector 25 changes depending on the state of the silicon film 101. The processing device 26 controls the shaping optical system 60 based on the detection signal from the photodetector 25. Specifically, the processing device 26 controls the pulse waveform so that the variation of the polysilicon film 101b is reduced. For example, the processing device 26 generates a control signal for controlling the pulse length and the like, and outputs it to the shaping optical system 60. As a result, the position of the mirror of the shaping optical system 60 is adjusted, and the pulse waveform changes.

[0044] In this way, the probe light L2 is irradiated onto the area immediately after irradiation with the laser light L1. That is, the probe light L2 is incident on the silicon film 101 in a molten state. Then, the photodetector 25 detects the probe light L3 that has passed through the substrate 100. Then, the processing device 26 determines the pulse waveform based on the detection signal from the photodetector 25. In this way, the ELA device 1 can set process conditions that can suppress uneven irradiation. The processing device 26 can determine optimal process conditions for the annealing process. The ELA device 1 executes the annealing process on the production substrate 100 under the set process conditions. A stable annealing process can be realized. In this way, productivity can be improved.

[0045] The process conditions for laser annealing are not limited to the pulse waveform. For example, the process conditions may be the peak intensity, repetition frequency, spatial distribution, polarization state, etc. of the laser light L1. Furthermore, the transport speed of the substrate 100 and the inclination angle of the line beam from the transport direction may be the process conditions. Furthermore, a plurality of substrates 100 may be processed to set optimal process conditions.

[0046] An optical system module 40 is disposed above the substrate 100. The optical system module 40 is equipped with at least a part of the above-mentioned optical system. Specifically, the optical system module 40 includes a mirror 19, a shaping optical system 60, a mirror 12, and a projection lens 13. The optical system module 40 is installed in a chamber 50.

[0047] Alternatively, as described above, the substrate 100 may be irradiated with a plurality of probe lights L2. Then, the photodetector 25 detects each of the plurality of probe lights L3 transmitted through the substrate 100. In this case, a plurality of photodetectors 25 corresponding to the plurality of probe lights L3 may be disposed below the substrate 100. Then, the processing device 26 sets process conditions based on, for example, an average value of the detection signals of the plurality of probe lights L3. This allows the annealing process to be performed under more suitable process conditions.

[0048] Embodiment 2 The configuration of the ELA apparatus 1 according to this embodiment will be described with reference to FIG. 4. FIG. 4 is a side view that shows a schematic configuration of the ELA apparatus 1. The ELA apparatus 1 of this embodiment differs from the first embodiment in that the laser light L1 and the probe light L2 are not coaxial. Note that the main configuration of the ELA apparatus 1 is the same as that of the first embodiment, and therefore the description will be omitted as appropriate. For example, the laser light source 11, the mirror 12, the shaping optical system 60, etc. are omitted in FIG. 4.

[0049] The probe light L2 from the probe light source 21 is incident on the mirror 22. The mirror 22 is disposed above the substrate 100. The mirror 22 reflects the probe light L2 toward the substrate 100. The probe light L2 reflected by the mirror 22 is focused on the substrate 100 by the lens 28. Therefore, as shown in FIG. 3, the probe light L2 forms a minute spot on the substrate 100. Note that since the probe light L2 is not coaxial with the laser light L1, the probe light L2 does not enter the projection lens 13. Therefore, the probe light L2 enters the substrate 100 from outside the projection lens 13.

[0050] The probe light L2 transmitted through the substrate 100 is referred to as probe light L3. The probe light L3 passes through an opening 43a of the floating unit 43 and enters the condenser lens 24. The condenser lens 24 condenses the probe light L3 on the light receiving surface of the photodetector 25. The probe light L3 from the condenser lens 24 enters the photodetector 25 via a filter 27.

[0051] In this configuration, too, appropriate process conditions for the laser light L1 can be set, as in the first embodiment. That is, the shaping optical system 60 shapes the pulse waveform of the laser light L1 based on the detection signal. This enables a stable annealing process and improves productivity. In the second embodiment, since the probe light L2 does not enter the mirror 12, the mirror 12 can be a metal reflecting mirror or a multilayer film reflecting mirror.

[0052] 1 and 4, the photodetector 25 is disposed below the substrate 100, and the probe light source 21 is disposed above it, but the probe light source 21 and the photodetector 25 may be disposed upside down. For example, the photodetector 25 may be disposed above the substrate 100, and the probe light source 21 may be disposed below the substrate 100. In this case, too, the probe light may or may not pass through the projection lens 13.

[0053] Third embodiment The configuration of the ELA apparatus 1 according to this embodiment will be described with reference to FIG. 5. FIG. 5 is a side view showing a schematic configuration of the ELA apparatus 1. The ELA apparatus 1 of this embodiment is different from the first and second embodiments in that the photodetector 25 detects the reflected light reflected by the substrate 100. In other words, the photodetector 25 does not detect the transmitted light transmitted through the substrate 100. Note that the description of the same configuration as the first and second embodiments will be omitted as appropriate. For example, the annealing optical system 10 is the same as the first embodiment, and the illumination optical system 20 is the same as the second embodiment, and therefore the description thereof will be omitted.

[0054] In the third embodiment, the detection optical system 30 is disposed above the substrate 100. Specifically, the condenser lens 24, the mirror 29, the filter 27, and the photodetector 25 are disposed above the chamber 50.

[0055] The light reflected by silicon film 101 is taken as probe light L4. Probe light L4 passes through window 51 and enters condenser lens 24. Probe light L4 from condenser lens 24 is reflected by mirror 29 and enters filter 27. Probe light L4 that passes through filter 27 enters photodetector 25. With this configuration as well, appropriate process conditions can be set, as in the first and second embodiments, enabling stable processing.

[0056] Furthermore, in this embodiment, a stage 46 that adsorbs the substrate 100 is used instead of the levitation unit 43. That is, the substrate 100 is placed on the stage 46. The stage 46 holds the substrate 100 by vacuum adsorption or the like. Furthermore, the stage 46 is a drive stage, and transports the substrate 100 in the X direction. Therefore, the irradiation positions of the laser light L1 and the probe light L2 on the substrate 100 change as the stage 46 moves. In this manner, the stage 46 forms a transport path along which the substrate 100 is transported.

[0057] Thus, in the third embodiment, the reflected light reflected by the substrate 100 serves as the probe light L4. Of course, the transmitted light transmitted through the substrate 100 may serve as the probe light L3 as in the first and second embodiments. That is, the photodetector 25 may detect the transmitted light transmitted through the substrate 100, or may detect the reflected light reflected by the substrate 100. Furthermore, two or more photodetectors 25 may be provided to detect both the transmitted light and the reflected light.

[0058] FIG. 6 is a graph showing the pulse waveform of the laser light L1 and the reflected light intensity (detected light amount of the probe light L4). The horizontal axis represents time, and the vertical axis represents the amount of light. As the silicon film 101 melts, the reflectivity increases, and therefore the reflected light intensity increases. Melting begins from the peak of the pulse waveform of the laser light L1, and so the reflected light intensity changes. The reflected light intensity reaches its maximum value immediately after the peak. The maximum value of the reflected light intensity indicates the maximum melted depth of the silicon. After reaching the maximum melted depth, solidification gradually progresses in the film thickness direction, and so the reflected light intensity gradually decreases. When the silicon is completely solidified, the reflected light intensity returns to the level before the pulsed light irradiation.

[0059] Then, the processing device 26 changes the process conditions so that the melting time becomes longer. The melting time is shown as the time from t1 to t2 in FIG. 6. A pulse waveform is set so that one shot of pulsed light keeps silicon in a molten state for a longer period of time. In other words, the process conditions of the pulse waveform are set so that the time t2 becomes later. In this way, a more stable annealing process is possible. Note that t2 corresponds to the timing at which the solidification of silicon progresses and the reflected light intensity falls below the threshold value.

[0060] The laser annealing method using the ELA apparatus according to the present embodiment may include the following steps (A) to (F). (A) A step of irradiating an amorphous semiconductor film formed on a substrate with laser light so as to crystallize the semiconductor film. (B) irradiating the semiconductor film after the laser light irradiation with a probe light. (C) detecting, with a photodetector, the transmitted light of the probe light transmitted through the substrate or the reflected light of the probe light reflected by the substrate. (D) transporting the substrate so as to change the irradiation position of the laser light and the probe light on the substrate; (E) setting process conditions for laser annealing based on a detection result by the photodetector when the substrate is transported. (F) performing laser annealing by irradiating the substrate with the laser light under the process conditions to crystallize the semiconductor film. This allows stable laser annealing.

[0061] The laser annealing method using the ELA apparatus according to this embodiment may include the following steps (STA) to (STH). (STA) A step of irradiating an amorphous semiconductor film formed on a substrate with laser light so as to crystallize the semiconductor film. (STB) A step of irradiating the semiconductor film after the laser light irradiation with a probe light. (STC) A step of detecting the transmitted light of the probe light transmitted through the substrate or the reflected light of the probe light reflected by the substrate with a photodetector. (STD) A step of extracting a portion of the laser light by a beam sampler disposed in the optical path of the laser light. (STE) A step of detecting the laser light extracted by the beam sampler with a laser light detector. (STF) A step of transporting the substrate so as to change the irradiation positions of the laser light and the probe light on the substrate. (STG) A step of setting process conditions for laser annealing based on the detection results of the photodetector and the laser photodetector when the substrate is transported. (STH) A step of performing laser annealing by irradiating the substrate with the laser light under the process conditions to crystallize the semiconductor film.

[0062] Furthermore, in setting the process conditions, a substrate dedicated to setting the conditions may be used, or an actual substrate on which an actual device is formed may be used. It is preferable to set the process conditions periodically. For example, the substrate 100 for setting the process conditions may be transported every few days or weeks, and laser annealing may be performed. Then, the process conditions are updated based on the latest measurement results.

[0063] The process conditions may be updated during the process. That is, the processing device 26 performs feedback based on the measurement results, thereby optimizing the process conditions during the process. This allows the ELA device 1 to perform laser annealing under optimal process conditions.

[0064] Fourth embodiment An ELA apparatus 1 according to a fourth embodiment will be described with reference to FIG. 7. FIG. 7 is a side view showing a schematic configuration of the ELA apparatus 1. In this embodiment, a lens 15 and a laser beam detector 16 are added to the annealing optical system 10. Furthermore, a beam sampler 14 that extracts a part of the laser beam is provided in place of the mirror 12 in the annealing optical system 10 and the illumination optical system 20. The basic configuration other than the beam sampler 14, the lens 15, and the laser beam detector 16 is the same as in the above-mentioned embodiments, and therefore description thereof will be omitted as appropriate.

[0065] A beam sampler 14 is disposed in the optical path of the laser light L1. Specifically, the beam sampler 14 is a partially transmitting mirror that transmits a portion of the incident light and reflects the remainder. For example, the beam sampler 14 has optical characteristics of high reflectance and low transmittance for the laser wavelength. Alternatively, the beam sampler 14 may be a perforated mirror with a small hole. In this way, the beam sampler 14 extracts a portion of the laser light L1. The beam sampler 14 reflects most of the laser light L1 toward the projection lens 13.

[0066] The laser light transmitted through the beam sampler 14 is defined as a light beam L5. The light beam L5 is incident on the laser light detector 16 via the lens 15. The lens 15 focuses the light beam L5 on the laser light detector 16. The laser light detector 16 is a photodiode or the like, and detects the light beam L5. The laser light detector 16 detects the light beam L5 and outputs a detection signal corresponding to the amount of detected light to the processing device 26.

[0067] The processing device 26 can detect the pulse waveform of the light beam L5. Then, the processing device 26 sets the process conditions based on the pulse waveform of the light beam L5. For example, the processing device 26 adjusts the process conditions so that the melting time shown in FIG. 6 is increased.

[0068] Specifically, a reference waveform that lengthens the melting time may be registered in advance in the processing device 26. Then, the processing device 26 sets process conditions so that the pulse waveform approaches the reference waveform. Specifically, the processing device 26 adjusts the peak intensity of the pulsed light. Alternatively, the processing device 26 adjusts the time interval between the first peak and the second hump shown in FIG. 5. In this way, stable annealing can be performed.

[0069] The pulse waveform adjustment by the processing device 26 will be described with reference to Fig. 8. Fig. 8 is a flow chart showing a method for adjusting the pulse waveform. It is assumed here that the laser light detector 16 detects the light beam L5 and the light detector 25 detects the probe light L3 as shown in Fig. 7. The processing device 26 detects the pulse waveform of the light beam L5 and the pulse waveform of the probe light L3 as shown in Fig. 6. The probe light L3 will be described as reflected light reflected by the substrate 100, but it may be transmitted light that has passed through the substrate 100.

[0070] First, the processing device 26 measures the melting time from the detection result of the probe light L3 (S101). As described above, when silicon melts, the reflectance increases and the transmittance decreases. Therefore, the processing device 26 can calculate the melting time from the detection result of the probe light L3. For example, as shown in FIG. 6, the melting time is the period from t1 to t2. t1 corresponds to the peak time of the light beam L5. t2 corresponds to the time when the reflected light intensity of the probe light L3 falls below the threshold level. Therefore, the period from t1 to t2 can be set as the melting time.

[0071] Next, the processing device 26 determines whether or not there has been a change in the melting time (S102). For example, the processing device 26 compares the melting time by the latest pulse irradiation with the melting time by the previous pulse irradiation to determine whether or not there has been a change in the melting time. Alternatively, the processing device 26 may detect a change in the melting time by comparing the melting time with a preset threshold time.

[0072] If there is no change in the melting time (NO in S102), the processing device 26 continues to measure the melting time. If there is a change in the melting time (YES in S102), the processing device 26 compares the pulse waveforms (S103). For example, a standard pulse waveform is pre-registered in the processing device 26. The standard pulse waveform is a waveform that can lengthen the melting time. The standard pulse waveform includes information regarding the time interval and intensity ratio between the first peak and the second hump shown in FIG. 6. The processing device 26 compares the measured pulse waveform with the standard pulse waveform.

[0073] Next, the processing device 26 calculates a correction method based on the comparison result (S104). For example, the processing device 26 performs a correction calculation to bring the measured pulse waveform closer to a standard pulse waveform. Specifically, the processing device 26 calculates a correction amount related to the time interval and intensity between the first peak and the second hump. The processing device 26 calculates the correction amount so that the pulse waveform comes closer to the standard pulse waveform. For example, the processing device 26 calculates a correction amount for the second hump so as to lengthen the time interval between the first peak and the second hump. Alternatively, the processing device 26 calculates a correction amount related to the intensity ratio of the first peak or the second hump.

[0074] Then, the processing device 26 corrects the pulse waveform (S105). For example, the processing device 26 outputs a correction signal to the laser light source 11 to change the laser light intensity or the like. The processing device 26 outputs a correction signal to the laser light source 11 to change the time interval between the first peak and the second hump. Alternatively, the processing device 26 outputs a correction signal to the laser light source 11 to change the laser light intensity. In this way, the ELA apparatus 1 can perform laser annealing under appropriate process conditions, and therefore, silicon can be stably crystallized.

[0075] (Pulse waveform adjustment) Next, a configuration for adjusting the pulse waveform will be described with reference to Fig. 9. Fig. 9 is a diagram showing a schematic configuration including two laser light sources 11a and 11b as the laser light source 11. Note that Fig. 9 shows the configuration up to the laser light source 11 and the shaping optical system 60. The laser light source 11a and the laser light source 11b are each a pulse laser light source and generate a pulse laser beam.

[0076] The laser light from the laser light source 11a is referred to as laser light L1a, and the laser light from the laser light source 11b is referred to as laser light L1b. The laser light L1a and the laser light L1b are incident on the beam splitter 17. The beam splitter 17 is a half mirror or the like, and combines the laser light L1a and the laser light L1b. The laser light L1a and the laser light L1b combined by the beam splitter 17 propagate coaxially. The laser light combined with the laser light L1a and the laser light L1b is referred to as laser light L1. The laser light L1 is incident on the shaping optical system 60. The shaping optical system 60 is the same as in the above embodiment, so a description thereof will be omitted.

[0077] The laser light L1 has a waveform obtained by combining two pulse lights. The peak of the laser light L1a corresponds to the first peak in FIG. 6, and the peak of the laser light L1b corresponds to the second hump in FIG. 6. The processing device 26 controls the laser light source 11a and the laser light source 11b independently. The processing device 26 controls the laser light source 11a and the laser light source 11b to adjust the pulse waveform. For example, the processing device 26 adjusts the laser light intensity by controlling the output of the laser light source 11a and the laser light source 11b. The melting time can be extended by adjusting the laser light intensity. That is, the processing device 26 adjusts the laser light intensity and the intensity ratio based on the detection result of the probe light L3 and the light beam L5. Therefore, the melting time can be extended, and a stable process can be achieved.

[0078] Alternatively, the processing device 26 can adjust the pulse waveform by controlling the oscillation timing of the laser light source 11a and the laser light source 11b. Alternatively, the processing device 26 can adjust the pulse waveform by changing the optical path length of at least one of the laser light L1a and the laser light L1b. By adjusting the oscillation timing or the optical path length, for example, the time between the first peak and the second hump can be changed. Therefore, the melting time can be extended, enabling a stable process.

[0079] Fig. 10 is a diagram showing another configuration for adjusting the pulse waveform. Fig. 10 shows a partial configuration of shaping optical system 60. Beam splitters 17a and 17b and mirrors 18a to 18c are provided in the optical path of shaping optical system 60. Beam splitters 17a and 17b are, for example, half mirrors.

[0080] A laser beam L11 from a laser light source 11 is split into two light beams L12 and L13 by a beam splitter 17a. The light beam L12 reflected by the beam splitter 17a is incident on a mirror 18a. The light beam L12 reflected by the mirror 18a is incident on a beam splitter 17b.

[0081] The light beam L13 transmitted through the beam splitter 17a directly enters the beam splitter 17b. The beam splitter 17b combines the light beams L12 and L13. The combined light beams are coaxially combined by the beam splitter 17b to form laser light L1. The laser light L1 from the beam splitter 17b enters the mirror 18c. The laser light L1 reflected by the mirror 18c enters the shaping optical system 60 shown in FIG. 1. The laser light L1 has a waveform obtained by combining two pulsed lights.

[0082] Here, since there is an optical path length difference between the light beam L12 and the light beam L13, the pulse of the light beam L12 is delayed from the pulse of the light beam L13. Then, the optical path length difference changes by changing the positions of the mirrors 18a and 18b. In other words, the processing device 26 can adjust the pulse waveform by controlling the positions of the mirrors 18a and 18b. For example, the processing device 26 can lengthen the optical path length of the light beam L12 by moving the mirrors 18a and 18b by the same distance in the +X direction.

[0083] The processing device 26 changes the optical path length based on the detection results of the probe light L3 and the light beam L5. This makes it possible to change, for example, the time between the first peak and the second hump. This makes it possible to lengthen the melting time and achieve a stable process.

[0084] Also, the laser light intensity can be adjusted in the configuration of Fig. 10. For example, multiple neutral density filters with different transmittances are prepared in advance. By changing the neutral density filters placed in the optical path, the laser light intensity and intensity ratio can be adjusted.

[0085] In this way, the ELA apparatus 1 according to the first to fourth embodiments irradiates the semiconductor film with the probe light L2 after the semiconductor film is irradiated with the laser light L1. Then, the photodetector 25 detects the probe light L4 reflected by the semiconductor film or the probe light L3 transmitted through the semiconductor film. Here, the timing of irradiating the semiconductor film with the probe light L2 may be after the laser light L1 is irradiated. That is, the probe light L2 may be irradiated onto the semiconductor film immediately after the start of irradiation of the pulsed laser light L1. As a result, the probe light L2 is irradiated onto the semiconductor film being irradiated with the laser light L1. Then, the photodetector 25 can detect the probe light from the semiconductor film in a molten state. The irradiation timing and irradiation position of the pulsed laser light L1 and the probe light L2 may at least partially overlap. That is, the probe light L2 may be irradiated onto the semiconductor film during irradiation of the laser light L1.

[0086] Alternatively, the irradiation position of the probe light L2 may be shifted downstream in the transport direction from the irradiation position of the laser light. In this case, the probe light L2 may be irradiated onto the semiconductor film immediately after the irradiation of the pulsed laser light L1 is completed. This allows the photodetector 25 to detect the probe light from the semiconductor film in a molten state. In other words, the irradiation timing and irradiation position of the pulsed laser light L1 and the probe light L2 may be shifted.

[0087] (OLED display) The semiconductor device having the polysilicon film is suitable for a TFT (Thin Film Transistor) array substrate for an organic EL (ElectroLuminescence) display. That is, the polysilicon film is used as a semiconductor layer having a source region, a channel region, and a drain region of the TFT.

[0088] Hereinafter, a configuration in which the semiconductor device according to the present embodiment is applied to an organic EL display will be described. Fig. 11 is a cross-sectional view showing a simplified pixel circuit of an organic EL display. The organic EL display 300 shown in Fig. 11 is an active matrix display device in which a TFT is arranged in each pixel PX.

[0089] The organic EL display 300 includes a substrate 310, a TFT layer 311, an organic layer 312, a color filter layer 313, and a sealing substrate 314. FIG. 11 shows a top-emission organic EL display in which the sealing substrate 314 side is the viewing side. Note that the following description shows one configuration example of an organic EL display, and the present embodiment is not limited to the configuration described below. For example, the semiconductor device according to the present embodiment may be used in a bottom-emission organic EL display.

[0090] The substrate 310 is a glass substrate or a metal substrate. A TFT layer 311 is provided on the substrate 310. The TFT layer 311 has a TFT 311a arranged in each pixel PX. The TFT layer 311 further has wiring (not shown) connected to the TFT 311a. The TFT 311a and the wiring constitute a pixel circuit.

[0091] An organic layer 312 is provided on the TFT layer 311. The organic layer 312 has an organic EL light emitting element 312a arranged for each pixel PX. Furthermore, the organic layer 312 is provided with partition walls 312b for separating the organic EL light emitting elements 312a between the pixels PX.

[0092] A color filter layer 313 is provided on the organic layer 312. The color filter layer 313 is provided with a color filter 313a for performing color display. That is, in each pixel PX, a resin layer colored with R (red), G (green), or B (blue) is provided as the color filter 313a.

[0093] A sealing substrate 314 is provided on the color filter layer 313. The sealing substrate 314 is a transparent substrate such as a glass substrate, and is provided to prevent the organic EL light emitting elements of the organic layer 312 from deteriorating.

[0094] The current flowing through the organic EL element 312a of the organic layer 312 varies depending on the display signal supplied to the pixel circuit. Therefore, by supplying a display signal corresponding to the display image to each pixel PX, the amount of light emitted by each pixel PX can be controlled. This allows a desired image to be displayed.

[0095] In an active matrix display device such as an organic EL display, one pixel PX is provided with one or more TFTs (e.g., a switching TFT or a driving TFT). The TFT of each pixel PX is provided with a semiconductor layer having a source region, a channel region, and a drain region. The polysilicon film according to this embodiment is suitable for the semiconductor layer of the TFT. That is, by using the polysilicon film manufactured by the above manufacturing method for the semiconductor layer of a TFT array substrate, it is possible to suppress in-plane variations in the TFT characteristics. Therefore, a display device with excellent display characteristics can be manufactured with high productivity.

[0096] <Semiconductor device manufacturing process> The manufacturing method of a semiconductor device using the laser annealing apparatus according to the present embodiment is suitable for manufacturing a TFT array substrate. The manufacturing method of a semiconductor device having a TFT will be described with reference to Figs. 12 and 13. Figs. 12 and 13 are cross-sectional views showing the manufacturing process of a semiconductor device. In the following description, a manufacturing method of a semiconductor device having an inverted staggered type TFT will be described. Figs. 12 and 13 show the process of forming a polysilicon film in the semiconductor manufacturing method. Note that the other manufacturing steps can be performed by using known techniques, and therefore the description will be omitted.

[0097] As shown in Fig. 12, a gate electrode 402 is formed on a glass substrate 401. A gate insulating film 403 is formed on the gate electrode 402. An amorphous silicon film 404 is formed on the gate insulating film 403. The amorphous silicon film 404 is disposed so as to overlap the gate electrode 402 with the gate insulating film 403 interposed therebetween. For example, the gate insulating film 403 and the amorphous silicon film 404 are successively formed by a CVD (Chemical Vapor Deposition) method.

[0098] Then, the amorphous silicon film 404 is irradiated with laser light L1 to form a polysilicon film 405 as shown in Fig. 13. That is, the amorphous silicon film 404 is crystallized by the ELA apparatus 1 shown in Figs. 1 to 6. As a result, a polysilicon film 405 made of crystallized silicon is formed on the gate insulating film 403. The polysilicon film 405 corresponds to the polysilicon film 101b described above.

[0099] The method for manufacturing a semiconductor device according to this embodiment may include the following steps. (S1) Step of setting process conditions for laser annealing. (S2) A step of forming an amorphous semiconductor film on a substrate. (S3) A step of performing laser annealing by irradiating the semiconductor film with laser light under the process conditions so as to crystallize the semiconductor film. The step of (S1) setting process conditions includes the following steps (a) to (e). (a) irradiating a semiconductor film formed on a substrate with laser light so as to crystallize the semiconductor film. (b) irradiating the semiconductor film after the laser light irradiation with a probe light. (c) detecting, with a photodetector, the transmitted light of the probe light that has been transmitted through the substrate or the reflected light of the probe light that has been reflected by the substrate. (d) transporting the substrate so as to change the irradiation position of the laser light and the probe light on the substrate; (e) setting process conditions for laser annealing based on a detection result by the photodetector when the substrate is transported. This allows stable laser annealing, thereby improving productivity.

[0100] The method for manufacturing a semiconductor device according to this embodiment may include the following steps. (S1) Step of setting process conditions for laser annealing. (S2) A step of forming an amorphous semiconductor film on a substrate. (S3) A step of performing laser annealing by irradiating the semiconductor film with laser light under the process conditions so as to crystallize the semiconductor film. The step of (S1) setting process conditions may comprise the steps of: (sta) A step of irradiating a semiconductor film formed on a substrate with laser light so as to crystallize the semiconductor film. (stb) A step of irradiating the semiconductor film after the laser light irradiation with a probe light. (stc) detecting, with a photodetector, the transmitted light of the probe light transmitted through the substrate or the reflected light of the probe light reflected by the substrate. (std) A step of extracting a portion of the laser light by a beam sampler disposed in the optical path of the laser light. (ste) A step of detecting the laser light extracted by the beam sampler with a laser light detector. (stf) A step of transporting the substrate so as to change the irradiation positions of the laser light and the probe light on the substrate. (stg) A step of setting process conditions for laser annealing based on detection results by the photodetector and the laser light detector when the substrate is transported.

[0101] Furthermore, in the above description, the laser annealing apparatus according to the present embodiment has been described as irradiating an amorphous silicon film with laser light to form a polysilicon film, but it may also be irradiating an amorphous silicon film with laser light to form a microcrystalline silicon film. Furthermore, the laser light used for annealing is not limited to an excimer laser, and may be an Nd:YAG laser or the like. The method according to the present embodiment can also be applied to a laser annealing apparatus that crystallizes a semiconductor film other than a silicon film. That is, the method according to the present embodiment can be applied to any laser annealing apparatus that irradiates a semiconductor film with laser light to crystallize the semiconductor film. The laser annealing apparatus according to the present embodiment can stably execute a laser annealing process.

[0102] The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0103] 1 ELA device 11 Laser light source 12. Mirror 13 Projection Lens 15 Lenses 16 Laser light detector 17a, 17b Beam splitter 18a, 18b mirror 20 Illumination optical system 21 Probe Light Source 22. Mirror 24 Condenser lens 25 Photodetector 26 Processing Equipment 27 Filters 28 Lenses 30 Detection optical system 40 Optical module 60 Molded optical system 100 Substrates 101 Silicone membrane 101a Amorphous silicon film 101b Polysilicon film 300 OLED display 310 Substrate 311 TFT layer 311a TFT 312 Organic layer 312a Organic EL light emitting device 312b Bulkhead 313 Color filter layer 313a Color filter (CF) 314 Sealing substrate 401 Glass Substrate 402 Gate electrode 403 Gate insulating film 404 Amorphous silicon film 405 Polysilicon film PX pixels

Claims

1. a laser light source that emits laser light for crystallizing an amorphous semiconductor film formed on a substrate; an annealing optical system that irradiates the semiconductor film with the laser light; a probe light source that emits a probe light; an optical system that irradiates the semiconductor film with the probe light after the semiconductor film has been irradiated with the laser light; a photodetector for detecting a transmitted light of the probe light transmitted through the substrate or a reflected light of the probe light reflected by the substrate; a transport path for transporting the substrate so as to change the irradiation position of the laser light and the probe light on the substrate; a processing unit that sets process conditions for laser annealing based on a detection result by the photodetector when the substrate is transported.

2. the laser beam is a pulsed laser beam, 2. The laser annealing apparatus according to claim 1, wherein the annealing optical system is provided with a shaping optical system that shapes a pulse waveform of the pulsed laser light.

3. the annealing optical system irradiates the substrate with the laser light so that the laser light forms a linear irradiation region on the substrate; an irradiation position of the probe light overlaps with the irradiation region on the substrate; The laser annealing apparatus according to claim 1 , wherein, in a plan view, a longitudinal direction of the irradiation region is inclined from a transport direction of the transport path.

4. the annealing optical system irradiates the semiconductor film with the laser light, thereby melting the semiconductor film; 4. The laser annealing apparatus according to claim 1, wherein the semiconductor film in a molten state is irradiated with the probe light.

5. (A) irradiating an amorphous semiconductor film formed on a substrate with laser light so as to crystallize the semiconductor film; (B) irradiating the semiconductor film with a probe light after the laser light is irradiated; (C) detecting, with a photodetector, a transmitted light of the probe light transmitted through the substrate or a reflected light of the probe light reflected by the substrate; (D) transporting the substrate so as to change the irradiation positions of the laser light and the probe light on the substrate; (E) setting process conditions for laser annealing based on a detection result by the photodetector when the substrate is transported; (F) performing laser annealing by irradiating the laser light to a substrate under the process conditions to crystallize the semiconductor film.

6. the laser beam is a pulsed laser beam, 6. The laser annealing method according to claim 5, wherein in the step (E), the process condition is a pulse waveform of the pulsed laser light being adjusted.

7. In the step (A), the laser light is irradiated onto the substrate so that the laser light forms a linear irradiation region on the substrate; an irradiation position of the probe light overlaps with the irradiation region on the substrate; The laser annealing method according to claim 5 , wherein, in a plan view, a longitudinal direction of the irradiation region is inclined from a transport direction of the substrate.

8. In the step (A), the semiconductor film is melted by irradiating the semiconductor film with the laser light, 8. The laser annealing method according to claim 5, wherein the semiconductor film in a molten state is irradiated with the probe light.

9. (S1) setting process conditions for laser annealing; (S2) forming an amorphous semiconductor film on a substrate; (S3) performing laser annealing by irradiating the semiconductor film with laser light under the process conditions so as to crystallize the semiconductor film; (S1) The step of setting process conditions includes: (a) irradiating a semiconductor film formed on a substrate with laser light so as to crystallize the semiconductor film; (b) irradiating the semiconductor film with a probe light after the laser light is irradiated; (c) detecting, with a photodetector, a transmitted light of the probe light transmitted through the substrate or a reflected light of the probe light reflected by the substrate; (d) transporting the substrate so as to change the irradiation positions of the laser light and the probe light on the substrate; (e) setting process conditions for laser annealing based on a detection result by the photodetector when the substrate is transported.

10. the laser beam is a pulsed laser beam, 10. The method for manufacturing a semiconductor device according to claim 9, wherein in the step (e), the process condition is a pulse waveform of the pulsed laser light being adjusted.

11. In the step (a), the laser light is irradiated onto the substrate so that the laser light forms a linear irradiation region on the substrate; an irradiation position of the probe light overlaps with the irradiation region on the substrate; The method for manufacturing a semiconductor device according to claim 9 , wherein a longitudinal direction of the irradiation region is inclined from a transport direction of the substrate in a plan view.

12. In the step (a), the semiconductor film is melted by irradiating the semiconductor film with the laser light; 12. The method for manufacturing a semiconductor device according to claim 9, wherein the semiconductor film in a molten state is irradiated with the probe light.

13. a laser light source that emits laser light for crystallizing an amorphous semiconductor film formed on a substrate; an annealing optical system that irradiates the semiconductor film with the laser light; a probe light source that emits a probe light; an optical system that irradiates the semiconductor film with the probe light after the semiconductor film has been irradiated with the laser light; a photodetector for detecting a transmitted light of the probe light transmitted through the substrate or a reflected light of the probe light reflected by the substrate; a transport path for transporting the substrate so as to change the irradiation position of the laser light and the probe light on the substrate; a beam sampler for extracting a portion of the laser light; a laser beam detector that detects the laser beam extracted by the beam sampler; a processing unit that sets process conditions for laser annealing based on detection results by the photodetector and the laser light detector when the substrate is transported.

14. the processing unit measures a melting time of the semiconductor film by irradiation with the laser light based on a detection result of the laser light detector; The laser annealing apparatus according to claim 13, wherein the pulse waveform of the laser light is adjusted so as to approach a reference waveform when the melting time changes.

15. the semiconductor film is irradiated with the laser light obtained by combining two pulsed laser lights; The laser annealing apparatus according to claim 14, wherein the pulse waveform is adjusted by changing an intensity or an optical path of at least one of the two pulsed laser beams.

16. (STA) irradiating a laser beam onto an amorphous semiconductor film formed on a substrate so as to crystallize the semiconductor film; (STB) irradiating the semiconductor film after the laser light irradiation with a probe light; (STC) detecting a transmitted light of the probe light transmitted through the substrate or a reflected light of the probe light reflected by the substrate with a photodetector; (STD) extracting a portion of the laser light by a beam sampler disposed in an optical path of the laser light; (STE) detecting the laser light extracted by the beam sampler with a laser light detector; (STF) transporting the substrate so as to change the irradiation position of the laser light and the probe light on the substrate; (STG) setting process conditions for laser annealing based on detection results by the photodetector and the laser light detector when the substrate is transported; (STH) A laser annealing method comprising: a step of performing laser annealing by irradiating a substrate with the laser light under the process conditions, thereby crystallizing the semiconductor film.

17. measuring a melting time of the semiconductor film by irradiation with the laser light based on a detection result by the laser light detector; 17. The laser annealing method according to claim 16, further comprising adjusting the pulse waveform of the laser light so as to approach a reference waveform when the melting time changes.

18. the semiconductor film is irradiated with the laser light obtained by combining two pulsed laser lights; The laser annealing method according to claim 17, wherein the pulse waveform is adjusted by changing an intensity or an optical path length of at least one of the two pulsed laser beams.

19. (S1) setting process conditions for laser annealing; (S2) forming an amorphous semiconductor film on a substrate; (S3) performing laser annealing by irradiating the semiconductor film with laser light under the process conditions so as to crystallize the semiconductor film; (S1) The step of setting process conditions includes: (sta) irradiating a semiconductor film formed on a substrate with laser light so as to crystallize the semiconductor film; (stb) irradiating the semiconductor film with a probe light after the laser light is irradiated; (stc) detecting, with a photodetector, a transmitted light of the probe light transmitted through the substrate or a reflected light of the probe light reflected by the substrate; (std) extracting a portion of the laser light by a beam sampler disposed in the optical path of the laser light; (ste) detecting the laser light extracted by the beam sampler with a laser light detector; (stf) transporting the substrate so as to change the irradiation positions of the laser light and the probe light on the substrate; (stg) setting process conditions for laser annealing based on detection results by the photodetector and the laser light detector when the substrate is transported.

20. measuring a melting time of the semiconductor film by irradiation with the laser light based on a detection result by the laser light detector; 20. The method for manufacturing a semiconductor device according to claim 19, wherein the pulse waveform of the laser light is adjusted so as to approach a reference waveform when the melting time changes.

21. the semiconductor film is irradiated with the laser light obtained by combining two pulsed laser lights; The method for manufacturing a semiconductor device according to claim 20 , wherein the pulse waveform is adjusted by changing an intensity or an optical path length of at least one of the two pulsed laser beams.

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