JP2005039250A - Device and method for laser beam irradiation and method of manufacturing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that, when a laser beam having higher harmonic waves is used for crystallizing a semiconductor film, the energy conversion efficiency of the higher harmonics is lower than that of the fundamental wave and, since the laser beam transformed into the higher harmonic waves is low in energy as compared with the laser beam having the fundamental wave, it becomes difficult to increase the throughput by widening the area of the beam spot. <P>SOLUTION: The laser beam irradiation device simultaneously projects a laser beam having a fundamental wave, and another laser beam having a wave of a wavelength equal to or shorter than that of the fundamental wave, typically, the higher harmonic waves transformed from the fundamental wave. The device projects the laser beams having the fundamental wave and the wave of the wavelength equal to or shorter than that of the fundamental wave emitted from one resonator without separating the laser beams from each other. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a laser irradiation apparatus used for crystallization of a semiconductor film. The present invention also relates to a method for manufacturing a semiconductor device including a step of crystallizing a semiconductor film using a laser irradiation apparatus.

A thin film transistor (TFT) using a crystalline semiconductor film has a mobility of two orders of magnitude higher than that of a TFT using an amorphous semiconductor film, and is formed over an inexpensive glass substrate by using a laser annealing method. Has the advantage of being able to.

Lasers are roughly classified into two types, pulse oscillation and continuous oscillation, depending on the oscillation method. A pulsed laser has a laser beam output energy per unit time, that is, a peak output that is about 3 to 6 digits higher than that of a continuous wave laser. Therefore, the beam spot (region where the laser beam is actually irradiated on the surface of the object to be processed) is shaped by an optical system so as to be a rectangular shape of several centimeters square or a linear shape having a length of 100 mm or more, and a semiconductor film It is possible to efficiently irradiate the laser beam and increase the throughput.

However, unlike a material and thickness of the absorption coefficient of the laser beam is a semiconductor film for a semiconductor film, when crystallizing the several tens to several hundreds nm thick silicon film YAG laser or a YVO ₄ laser, wavelength than the fundamental wave Since the short second harmonic has a higher absorption coefficient, crystallization can be performed efficiently. In order to emit harmonics, a fundamental wave is oscillated and converted through a harmonic generator or the like. And the fundamental wave and the harmonic are separated (refer patent document 1).
JP 2001-156018 A

In addition to laser crystallization, solid-state lasers are used for physics and chemistry (light source of spectroscopic measurement device), optical fiber communication, metal processing (laser welding) and the like.

In the case of physics and chemistry and optical fiber communication, since it is premised on use at a single wavelength, it is natural to separate and use the fundamental wave and harmonics. In the case of metal processing, since the metal absorbs the fundamental wave, it may be used for the processing with the fundamental wave, and there is no need to bother converting it into a harmonic wave. For this reason, a commercially available solid-state laser emits only the fundamental wave or after separating the fundamental wave and the harmonics.

Even in the field of laser crystallization equipment, the fundamental wave has not been absorbed by a semiconductor film having solid-state silicon so far, and when used for laser crystallization, harmonics absorbed by a semiconductor film having silicon in a solid state are used. It was the mainstream to separate and use alone. That is, since the semiconductor film does not absorb the oscillation wavelength (fundamental wave) of the solid-state laser, when it is used for laser annealing, the second harmonic, the third harmonic, or more when the wavelength falls from the visible light region to the ultraviolet light region. The higher harmonics are used.

However, the problem is that the energy conversion efficiency of harmonics with respect to the fundamental wave is low. For example, in the case of an Nd: YAG laser, the conversion efficiency from the fundamental wave (wavelength: 1064 nm) to the second harmonic (wavelength: 532 nm) is around 50%.

In addition, since the nonlinear optical element that converts to harmonics is extremely low in resistance to laser light, it is difficult to increase the output of the fundamental wave. For example, a continuous wave YAG laser can output a fundamental wave of 10 kW, whereas an output of the second harmonic can be obtained only about 10 W considering the tolerance of the nonlinear optical element.

Therefore, in order to obtain the energy density necessary for crystallization of the semiconductor film, the area of the beam spot must be reduced to about 10 ⁻³ mm ^2, which is inferior in terms of throughput. Since the laser light converted into the harmonic has lower energy than that of the fundamental wave, it is difficult to increase the beam spot area and increase the throughput. In particular, this tendency is remarkable in the continuous wave laser because the output of the laser beam per unit time is lower than that of the pulsed laser.

Therefore, the present invention proposes a new laser annealing method and an object thereof is to provide a method for efficiently crystallizing a semiconductor film. Another object of the present invention is to provide a method for manufacturing a semiconductor device having a crystalline semiconductor film formed by a new laser annealing method.

In view of the above problems, the present inventor has found a method of irradiating an object to be irradiated (also expressed as an object to be processed) without separating the fundamental wave and the harmonic. That is, the present invention relates to a laser irradiation apparatus (laser annealing apparatus) for irradiating an irradiation object with a fundamental wave of a laser and a wavelength shorter than the fundamental wave, and a fundamental wave emitted from one resonator (oscillator). The same irradiation surface is irradiated with laser light having a wavelength equal to or lower than the fundamental wave. In particular, the present invention is characterized in that the object to be irradiated is irradiated without separating the fundamental wave from one resonator and the wavelength below the fundamental wave.

Thus, by irradiating the irradiated object without separating the harmonic with low energy and the fundamental wave, laser irradiation (laser annealing) can be performed efficiently. In other words, since the irradiation is performed without separating the fundamental wave, the fundamental wave can be irradiated in an auxiliary manner with respect to the higher energy harmonic. In particular, the fundamental wave is preferable because it is easily absorbed by a semiconductor film containing silicon in a molten state. That is, a semiconductor film containing silicon in a molten state has a higher absorption coefficient of a fundamental wave than a solid phase state, that is, a crystalline semiconductor film containing silicon.

In order to achieve the present invention, a laser irradiation apparatus is configured to relatively combine a laser resonator that outputs a fundamental wave and a wavelength equal to or less than the fundamental wave, an object to be irradiated, and a laser beam from the laser resonator. Means for moving, and means for processing the laser beam into a linear laser. Further, the means for processing the linear laser has means for condensing (focusing) laser light having a fundamental wave and a wavelength equal to or less than the fundamental wave. In the present invention, the laser beam output from the laser resonator may be either a pulse oscillation type or a continuous oscillation type.

“Linear” does not mean “line” in a strict sense, but means a rectangle (or oval) having a large aspect ratio. For example, an aspect ratio of 2 or more (preferably 10 to 10000) is called a linear shape, but the linear shape is still included in a rectangular shape.

The laser medium (medium) included in the laser resonator of the present invention includes YAG, YLF, YVO ₄ , Y ₂ O ₃ , glass, sapphire, and forsterite doped with ions such as Nd, Yb, Ti, Cr, Ho, and Er. (Forsterite), LuAg, and LuLiF ₄ solids are utilized. A laser using a solid as such a laser medium is referred to as a solid laser.

  The wavelength below the fundamental wave is, for example, a harmonic of the fundamental wave, which is twice the harmonic (second harmonic), three times the harmonic (third harmonic), and four times the harmonic (fourth harmonic). Harmonics). Since the main oscillation wavelength of the solid-state laser is in the infrared region, the harmonics are mainly in the visible light region. That is, wavelengths below the fundamental wave can be expressed as wavelengths that are comparable to or shorter than visible light.

Examples of the second harmonic wavelength of a typical solid-state laser are as follows: Nd: YAG laser: 532 nm, Nd: YVO ₄ laser: 532 nm, Nd: YLF laser: 527 nm (or 524 nm), Ti: sapphire laser: 345 ˜550 nm (tunable wavelength), alexandrite laser: 350 to 410 nm (tunable wavelength).

In order to convert a fundamental wave into a harmonic, a non-linear optical element such as SHG (Second Harmonic Generation) or THG (Third Harmonic Generation) is used. For example, as SHG, KTP (KTiOPO ₄ ), BBO (β-BaB ₂ O ₄ ), LBO (LiB ₃ O ₅ ), CLBO (CsLiB ₆ O ₁₀ ), GdYCOB (GdYCa ₄ O (BO) having relatively large nonlinear optical constants. ₃ ) Crystals such as ₃ ), KDP (KD ₂ PO ₄ ), KB ₅ , LiNbO ₃ , Ba ₂ NaNb ₅ O ₁₅ are used, and in particular, LBO, BBO, KDP, KTP, KB5, CLBO, etc. should be used. Thus, the conversion efficiency from the fundamental wave to the harmonic can be increased.

In the present invention, laser irradiation may be performed obliquely with respect to the surface of the workpiece. At this time, the length of the major or minor axis of the laser beam processed into a linear shape on the surface of the object to be irradiated is W, the thickness of the substrate on which the object to be irradiated is placed, which is transparent to the laser beam. When the height is d, the laser beam is irradiated so that the incident angle φ satisfies φ ≧ arctan (W / 2d). By irradiating laser light obliquely with an incident angle in this way, interference of laser light on the object to be processed can be prevented, and more uniform laser annealing can be performed.

Since the laser irradiation apparatus of the present invention irradiates the fundamental wave and the harmonics from one resonator without separating them, only one resonator is required. Therefore, the running cost of the resonator can be reduced. In addition, optical adjustment is easier than in the case where laser light having a fundamental wave and laser light having harmonics are oscillated from individual resonators and laser light is combined on the irradiation surface. Since the processing to the linear laser is performed by the same optical system, the optical system can be simplified. Of course, a lens or the like for separating the fundamental wave and the harmonic wave is not necessary.

When laser annealing is performed using laser light having a fundamental wave and a harmonic wave, the semiconductor film is melted by the harmonic wave, and the absorption coefficient of the fundamental wave into the semiconductor film is dramatically increased. It is thought that it becomes easy to be absorbed.

Therefore, by irradiating the harmonics and the fundamental wave without separating them, the region to be annealed, that is, the region where the crystallinity is good, becomes large, improving the throughput and obtaining a high-quality crystalline semiconductor film. Can do.

Through the above steps, a high-performance thin film transistor and a semiconductor device including the thin film transistor can be manufactured with high throughput and low cost.

Since the laser irradiation apparatus of the present invention irradiates the fundamental wave and the harmonics from one resonator without separating them, only one resonator is required. Therefore, the running cost of the resonator can be reduced. In addition, since it is not necessary to oscillate laser light having a fundamental wave and laser light having a harmonic from individual resonators and align the laser light on the irradiation surface, optical adjustment is easy. Since the processing to the linear laser is performed by the same optical system, the optical system can be simplified.

Furthermore, in the present invention, laser irradiation can be performed efficiently by irradiating the harmonics having low energy and the fundamental wave without separating them, and the region to be annealed, that is, the region where the crystallinity is good becomes large. Throughput can be expected.

As described above, a highly functional thin film transistor and a semiconductor device including the thin film transistor can be manufactured with high throughput and low cost.

Embodiments of the present invention will be described below with reference to the drawings. However, the present invention can be implemented in many different modes, and it is easy for those skilled in the art to make various changes in form and details without departing from the spirit and scope of the present invention. Understood. Therefore, the present invention is not construed as being limited to the description of this embodiment mode. Note that in all the drawings for describing the embodiments, the same portions or portions having similar functions are denoted by the same reference numerals, and repetitive description thereof is omitted.

(Embodiment 1)
In this embodiment mode, a specific laser irradiation apparatus will be described.

FIG. 1 shows a laser resonator 101 having an excitation source, a laser medium, and a nonlinear optical element, an optical system 102 including a cylindrical lens array, a first reflector 103, a second reflector 104, a fundamental wave, A condenser 105 that focuses both wavelengths of the second harmonic, a stage 107 that fixes the irradiated object 106, a uniaxial robot 108 for the X axis that is a means for moving the stage, and a uniaxial robot 109 for the Y axis. The laser annealing apparatus which has is shown.

In this embodiment, the case where the laser resonator is an internal conversion type in which a nonlinear optical element is incorporated is illustrated, but an external conversion type in which the nonlinear optical element is provided outside the laser resonator may be used. The optical system 102 includes a homogenizer configured with a cylindrical lens or the like. The first and second reflectors and the light collector 105 may be provided at predetermined positions as necessary.

In addition, since the light collector 105 needs to focus both wavelengths of the fundamental wave and the second harmonic, a reflector having a curved surface such as a concave mirror can be used. When a concave mirror or the like is used, all laser light is reflected without chromatic aberration without depending on the wavelength, and the laser light can be focused on the irradiation surface. Furthermore, the cost can be reduced. Further, instead of the concave mirror, an achromatic lens or the like that can correct chromatic aberration may be used. In FIG. 1, laser light can be directly incident on the light collector 105 from the optical system 102 to irradiate the irradiated object with a linear laser.

That is, the optical system 102 and the condenser 105 correspond to one means for processing laser light into a linear laser on the irradiation surface. Note that a linear laser can be processed even if a plurality of cylindrical lenses are installed or combined with a convex lens or a concave lens.

A laser having a pulse oscillation power of 200 to 300 W, such as an Nd: YAG laser, emits a fundamental wave having an oscillation wavelength of 1064 nm and a second harmonic having an oscillation wavelength of 532 nm from the laser resonator 101 without separation. . Strictly speaking, a fundamental wave is oscillated from a laser resonator, converted from a fundamental wave to a harmonic, and laser light having both wavelengths is emitted. At this time, the frequency of the fundamental wave and the second harmonic is 1 KHz, and the pulse width is about 120 ns.

The laser beam is preferably in a TEM ₀₀ mode (single mode) obtained from a stable resonator. In the case of the TEM ₀₀ mode, the laser beam has a Gaussian intensity distribution and has excellent light collecting properties, so that the beam spot can be easily processed.

The beam spot shape of the laser beam is processed by the optical system 102 and is formed so that the energy distribution becomes uniform on the surface (irradiation surface) of the irradiation object 106. The laser light is reflected by the first reflector 103 and the second reflector 104 as necessary, and the traveling direction is changed. Then, the irradiated object 106 is irradiated through the light collector 105. A mirror can be used for the first and second reflectors.

In particular, the laser beam can be transmitted through the condenser 105 so that the linear laser 110 can be focused on the irradiated surface. The shape of the linear laser on the irradiated surface, that is, the beam spot is, for example, the linear laser 110 having a length of about 100 mm and a width of about 20 μm. Such a linear laser can perform a large area process. As a result, the throughput of the laser annealing process can be improved.

In this embodiment, a substrate over which a semiconductor film is formed as the object 106 is set so as to be parallel to a horizontal plane. The semiconductor film is formed on a glass substrate having a thickness of 0.7 mm. In order to prevent the substrate from falling during laser irradiation, the stage 107 is provided with an adsorption mechanism to fix the substrate. By the suction mechanism, the substrate can be fixed so as to reduce the deflection of the substrate. Further, laser processing can be performed in a state where the substrate is fixed so as to be bent into a predetermined shape.

The stage 107 can move in the XY direction on a plane parallel to the irradiation surface by the uniaxial robot 108 for the X axis and the uniaxial robot 109 for the Y axis. In other words, the X-axis single-axis robot 108 and the Y-axis single-axis robot 109 correspond to means for relatively moving the irradiated object 106 and the laser beam.

Using such a laser irradiation apparatus, laser annealing is performed by setting the substrate feed pitch for each pulse to about 1 to 30 μm. In this embodiment mode, laser annealing is performed with a thickness of 5 μm.

Next, the scanning path of the beam spot 110 on the surface of the workpiece 106 will be described. In the case of irradiating the entire surface of the semiconductor film as the workpiece 106 with laser light, after scanning in one direction using the Y-axis robot 109, the X-axis robot 108 is used to scan in the scanning direction by the Y-axis robot 109. The beam spot 110 is slid in a direction perpendicular to the direction. By repeating the scanning by the Y-axis robot 109 and the scanning by the X-axis robot 108 in order, the entire surface of the workpiece 106 can be irradiated with laser light.

A region where crystal grains that have been irradiated with laser light and grown in the scanning direction are formed has excellent crystallinity. Therefore, by using this region as a TFT channel formation region, extremely high electric mobility and on-current can be expected. However, when there is a portion of the crystalline semiconductor film that does not require such high crystallinity, the laser light may not be irradiated. Alternatively, laser light irradiation may be performed under such conditions that high crystallinity cannot be obtained, such as by increasing the scanning speed. Thus, the throughput can be further increased by partially increasing the scanning speed.

The scanning of the laser beam includes an irradiation system moving type that fixes the substrate as the object to be processed and moves the irradiation position of the laser light, and an object movement type that fixes the irradiation position of the laser light and moves the substrate. And a combination of the above two methods. The laser irradiation apparatus of the present embodiment is suitably a workpiece moving type that can simplify the configuration of the optical system. However, the laser irradiation apparatus is not limited to this, and it is not impossible to make the irradiation system moving type by combining the optical system or to combine the object moving type and the irradiation system moving type. In any case, it is only necessary to control the relative movement direction of each laser beam, that is, the beam spot with respect to the semiconductor film.

As described above, since the fundamental wave and the harmonics from one resonator are irradiated without being separated, only one resonator is required. Therefore, the running cost of the resonator can be reduced. In addition, since it is not necessary to oscillate laser light having a fundamental wave and laser light having a harmonic from individual resonators and align the laser light on the irradiation surface, optical adjustment is easy. Since the processing to the linear laser is performed by the same optical system, the optical system can be simplified.

Further, in this embodiment, a high-quality crystalline semiconductor film can be obtained by combining a laser beam having a fundamental wave and a laser beam having a wavelength of visible light or less and laser annealing. As a result, a high-performance thin film transistor and a semiconductor device including the thin film transistor can be manufactured with high throughput and low cost.

As in this embodiment, a solid-state laser whose laser medium is solid is maintenance-free and has a stable output. In particular, a pulse laser is considered to be excellent in mass productivity because it can oscillate at a higher repetition rate than an excimer laser. However, the invention is not limited to the pulsed laser shown in this embodiment mode, and a continuous wave laser may be used.

Note that the optical system in the laser irradiation apparatus is not limited to the structure shown in this embodiment mode.

(Embodiment 2)
In this embodiment, a case where a continuous wave laser is used and laser irradiation is performed on the surface of an object to be processed from an oblique direction will be described.

FIG. 2 shows a laser resonator 101 having an excitation source, a laser medium, and a nonlinear optical element, an optical system 102 including a cylindrical lens array or diffractive optics, a first reflector 103, a condenser 120, and an irradiated object. 1 shows a laser annealing apparatus having a stage 107 for fixing 106, a uniaxial robot 108 for X axis as means for moving the stage, and a uniaxial robot 109 for Y axis.

In FIG. 2, in order to irradiate a laser beam on the surface of the workpiece from an oblique direction, the incident angle of the laser is tilted with respect to the workpiece, but a uniaxial robot for the φ axis is provided and the stage 107 is tilted. May be.

In this embodiment, the case where the laser resonator is an internal conversion type in which a nonlinear optical element is incorporated is illustrated, but an external conversion type in which the nonlinear optical element is provided outside the laser resonator may be used. The optical system 102 may include a homogenizer composed of a cylindrical lens or a diffractive optics, and may divide the laser.

The condensing body 120 needs to focus both wavelengths of the fundamental wave and the second harmonic, so that an achromatic lens or the like having no chromatic aberration can be used. Further, as in the first embodiment, a reflector having a curved surface such as a concave mirror may be used.

A laser having a continuous oscillation power of 200 to 300 W, such as an Nd: YAG laser, emits a fundamental wave having an oscillation wavelength of 1064 nm and a second harmonic having a wavelength of 532 nm from the laser resonator 101 without separation. Strictly speaking, a fundamental wave is oscillated from a laser resonator, converted from a fundamental wave to a harmonic, and a laser beam having both wavelengths is emitted.

In such a continuous wave laser irradiation method, the scanning speed of the beam spot 110 is suitably about several cm / s to several hundred cm / s. In this embodiment, it is 50 cm / s.

Thus, the present invention may use a continuous wave laser. By irradiating the harmonics with low energy and the fundamental wave without separating them, laser irradiation can be performed efficiently, and the area to be annealed, that is, the area where the crystallinity is good becomes large, and the throughput is increased. Improvement can be expected.

In addition, the present embodiment is characterized in that the irradiated object 106 is irradiated with laser light at an incident angle φ. In this case, the length of the major axis or minor axis on the surface of the irradiated object of the laser light processed into a linear shape is W, the substrate is transparent to the laser light, and the substrate is provided with the irradiated object Is d so that the incident angle φ of the laser beam satisfies φ ≧ arctan (W / 2d). Note that the reflector 103 and the condenser 120 correspond to a means for controlling the incident angle φ of the laser beam to satisfy φ ≧ arctan (W / 2d). For example, a cylindrical lens can be used as the light collector.

If the laser light is incident at this incident angle degree φ, the reflected light from the surface of the substrate and the reflected light from the back surface of the substrate do not interfere with each other, and uniform laser light irradiation can be performed. In the above discussion, the refractive index of the substrate was considered as 1. Actually, in many cases, the refractive index of the substrate is around 1.5, and if this value is taken into consideration, a calculated value larger than the calculated angle can be obtained. However, since the energy of the beam spot is attenuated as it approaches the end of the beam spot, the influence of the interference in this portion is small, and the effect of interference attenuation can be sufficiently obtained by the above calculated value. This argument indicates that there is no problem even if the above inequality is not satisfied for an extremely short coherent laser.

The above inequality for φ is applied only when the substrate is transparent to laser light. Note that the glass substrate is transparent to a fundamental wave such as YAG having a wavelength of about 1 μm and the second harmonic.

The laser irradiation apparatus of the present embodiment is suitably a workpiece moving type that can simplify the configuration of the optical system. However, as in the first embodiment, it is not impossible to devise an optical system so that an irradiation system movement type or a combination of an object movement type and an irradiation system movement type is possible. In any case, it is sufficient that the relative movement direction of each beam spot with respect to the semiconductor film can be controlled.

Since the laser irradiation apparatus of this embodiment irradiates the fundamental wave and harmonics from one resonator without separating them, only one resonator is required. Therefore, the running cost of the resonator can be reduced. In addition, since it is not necessary to oscillate laser light having a fundamental wave and laser light having a harmonic from individual resonators and align the laser light on the irradiation surface, optical adjustment is easy. Since the processing to the linear laser is performed by the same optical system, the optical system can be simplified.

Through the above steps, a high-performance thin film transistor and a semiconductor device including the thin film transistor can be manufactured with high throughput and low cost.

Note that the optical system in the laser irradiation apparatus is not limited to the structure shown in this embodiment mode. In this embodiment mode, a continuous wave laser is described, but a pulsed laser may be used.

(Embodiment 3)
In this embodiment, the entire system of the laser irradiation apparatus will be described.

FIG. 3 shows the entire system of the laser irradiation apparatus. In the present embodiment, laser light having a fundamental wave and a wavelength shorter than the fundamental wave of pulse oscillation is oscillated from the laser resonator 300.

Laser light oscillated from the laser resonator 300 has a fundamental wave and a laser converted into a second harmonic by a nonlinear optical element, and is incident on the beam expander 301. The beam expander 301 suppresses the spread of the incident laser light and adjusts the size of the cross-sectional shape of the beam.

The laser light emitted from the beam expander 301 is processed by the cylindrical lens 302 so that the cross-sectional shape of the beam becomes rectangular, elliptical, or linear. Then, the laser light is reflected by a concave mirror 303 corresponding to a condenser, is condensed in a linear shape, and is irradiated onto the object to be processed 306 in the laser irradiation chamber 305.

As described above, the laser beam having the fundamental wave and the harmonic can make up for the energy shortage of the harmonic and can efficiently form an irradiation object with high crystallinity, for example, a semiconductor film. Moreover, an irradiation surface can be enlarged by irradiating a fundamental wave and a harmonic.

In the laser irradiation chamber 305, the workpiece 306 is disposed on a stage 307, and the position of the stage 307 is controlled by uniaxial robots 308 to 310 serving as three position control means. Specifically, the stage 307 can be rotated in the horizontal plane by the uniaxial robot 308 for the φ axis. It can be tilted from the horizontal plane. Further, the stage 307 can be moved in the X-axis direction by the single-axis robot 309 for the X-axis. Further, the stage 307 can be moved in the Y-axis direction by the single-axis robot 310 for the Y-axis. The stage 307 itself may be tilted. The operation of each position control means is controlled by the central processing unit 311.

By irradiating the object to be processed in the X direction while irradiating a linear beam spot elongated in the Y-axis direction, a collection of crystal grains elongated in the scanning direction can be formed. In the case of a continuous wave laser, the scanning speed may be, for example, 10 to 2000 mm / s, preferably 100 to 1000 mm / s. The beam width may be several hundred μm to 1 mm. Thereby, crystal grains grown in the scanning direction can be formed in a region having a width of 100 mm in the direction perpendicular to the scanning direction. In the case of a pulse oscillation laser, the substrate feed pitch for each pulse may be set to 1 to 30 μm.

Note that as in this embodiment, a monitor 312 using a light receiving element such as a CCD may be provided so that the position of the workpiece 306 can be accurately grasped.

By using such a laser irradiation apparatus system, laser processing based on accurate position control can be performed. Furthermore, the stage can be fixed in a horizontal state or an inclined state, and laser irradiation from a vertical direction or an oblique direction can be performed. The stage itself may be tilted.

(Embodiment 4)
In this embodiment, a laser irradiation method and a method for manufacturing a semiconductor device will be described.

First, as illustrated in FIG. 4A, base films 401a and 401b are formed over a substrate 400 having an insulating surface. As the substrate 400, for example, a glass substrate such as barium borosilicate glass or alumino borosilicate glass, a quartz substrate, a SUS substrate, or the like can be used. In addition, plastics typified by PET, PES, and PEN, and substrates made of a synthetic resin having flexibility such as acrylic generally tend to have a lower heat resistant temperature than other substrates. Any material can be used as long as it can withstand the processing temperature.

The base films 401a and 401b are provided to prevent alkali metal such as Na or alkaline earth metal contained in the substrate 400 from diffusing into the semiconductor film and adversely affecting the characteristics of the semiconductor element. Therefore, the insulating film is formed using an insulating film such as silicon oxide, silicon nitride, or silicon nitride oxide that can suppress diffusion of alkali metal or alkaline earth metal into the semiconductor film. In this embodiment mode, a silicon oxynitride film is stacked in a thickness of 10 to 200 nm (preferably 50 to 100 nm) and a silicon oxynitride film is stacked in order of 50 to 200 nm (preferably 100 to 150 nm) by a plasma CVD method. Note that the base film 401 may be a single layer.

When using a substrate that contains alkali metal or alkaline earth metal, such as a glass substrate, a SUS substrate, or a plastic substrate, it is effective to provide a base film from the viewpoint of preventing diffusion of impurities. In the case where diffusion of impurities does not cause any problem, such as a quartz substrate, it is not necessarily provided.

An amorphous semiconductor film 402 is formed over the base film 401b. The thickness of the amorphous semiconductor film 402 is 25 to 100 nm (preferably 30 to 60 nm). As the amorphous semiconductor, not only silicon but also silicon germanium can be used. When silicon germanium is used, the concentration of germanium is preferably about 0.01 to 4.5 atomic%.

Next, as shown in FIG. 4B, crystallization is performed by irradiating the amorphous semiconductor film 402 with laser light 405 using the laser irradiation apparatus of the present invention.

In this embodiment, a 200 W fundamental wave, a 10 W second harmonic, and a TEM ₀₀ mode oscillation Nd: YVO ₄ laser is used as the laser light. Note that the first beam spot formed on the surface of the amorphous semiconductor film 402 by processing laser light with an optical system is a rectangular shape having a short axis of 20 μm and a long axis of 10 mm.

Then, laser light is scanned on the surface of the amorphous semiconductor film 402 in the direction of the arrow illustrated in FIG. The crystal grains continuously grown in the scanning direction are formed by the laser light irradiation. By forming crystal grains that extend long along the scanning direction, it is possible to form a crystalline semiconductor film 403 having almost no crystal grain boundaries in at least the channel direction of the TFT.

Note that laser light may be irradiated in an inert gas atmosphere such as a rare gas or nitrogen. Thereby, roughness of the semiconductor surface due to laser light irradiation can be suppressed, and variation in threshold value caused by variation in interface state density can be suppressed.

Next, as illustrated in FIG. 4C, the crystalline semiconductor film 403 is patterned to form island-shaped semiconductor films 406a to 406d. Various islands represented by TFTs using the island-shaped semiconductor films 406a to 406d are formed. The semiconductor element is formed.

Next, although not illustrated, a gate insulating film is formed so as to cover the island-shaped semiconductor films 406a to 406d. For the gate insulating film, for example, silicon oxide, silicon nitride, silicon nitride oxide, or the like can be used. As a film formation method, a plasma CVD method, a sputtering method, or the like can be used.

Next, a conductive film is formed on the gate insulating film and patterned to form a gate electrode. Then, using a gate electrode or a resist formed and patterned as a mask, an impurity imparting n-type or p-type conductivity is added to the island-shaped semiconductor films 406a to 406d, and the source region, the drain region, Forms an LDD region and the like.

A TFT can be formed by the above-described process. Note that the method for manufacturing a semiconductor device of the present invention is not limited to the above-described TFT manufacturing process. The present invention is characterized in that a crystalline semiconductor film obtained by using a laser beam irradiation method is used as an active layer of a TFT. As a result, variations in mobility, threshold value, and on-current between elements can be suppressed.

Note that laser light is not limited to the irradiation conditions described in this embodiment mode.

Further, a crystallization step using a catalytic element may be provided before crystallization with laser light. Nickel (Ni) is used as the catalyst element, but besides that, germanium (Ge), iron (Fe), palladium (Pd), tin (Sn), lead (Pb), cobalt (Co), Elements such as platinum (Pt), copper (Cu), and gold (Au) can be used. When a crystallization process using a laser beam is performed after a crystallization process using a catalytic element, the crystal formed during crystallization using the catalytic element remains without being melted by the irradiation of the laser beam. Crystallization proceeds as a crystal nucleus. Therefore, the crystallinity of the semiconductor film can be further increased as compared with the case of only the crystallization process using laser light, and the roughness of the surface of the semiconductor film after crystallization using laser light can be suppressed. Accordingly, variation in characteristics of semiconductor elements formed later, typically TFTs, can be further suppressed, and off-current can be suppressed.

Note that after the catalyst element is added and heat treatment is performed to promote crystallization, the crystallinity may be further increased by laser light irradiation, or the heat treatment step may be omitted. Specifically, after adding the catalyst element, laser light may be irradiated instead of the heat treatment to improve crystallinity.

Note that although an example in which the laser irradiation method of the present invention is used for crystallization of a semiconductor film is described in this embodiment mode, the semiconductor film may be used to activate an impurity element doped in the semiconductor film.

The method for manufacturing a semiconductor device of the present invention can be used for a method for manufacturing an integrated circuit or a semiconductor display device. In particular, a liquid crystal display device, a light emitting device including a light emitting element typified by an organic light emitting element in each pixel, a semiconductor display device such as a DMD (Digital Micromirror Device), a PDP (Plasma Display Panel), and an FED (Field Emission Display). It can be used for a semiconductor element such as a transistor provided in the pixel portion.

(Embodiment 5)
In this embodiment, a light-emitting device manufactured using a laser irradiation method will be described.

FIG. 5A illustrates a light-emitting device in which a signal line driver circuit 1200, a scan line driver circuit 1201, and a pixel portion 1202 are formed over a first substrate 1210.

5B is a cross-sectional view taken along line AA ′ of the display device. A signal line driver circuit 1200 including a CMOS circuit having an n-channel TFT 1223 and a p-channel TFT 1224 over a first substrate 1210 is shown. Show. The n-channel TFT 1223 and the p-channel TFT 1224 have a high-quality crystalline semiconductor film by synthesizing a laser beam having a fundamental wave and a laser beam having a wavelength less than or equal to visible light, and performing laser annealing. Formed. The TFTs forming the signal line driver circuit 1200 and the scanning line driver circuit 1201 may be formed of a CMOS circuit, a PMOS circuit, or an NMOS circuit.

The pixel portion 1202 includes a switching TFT 1211 and a driving TFT 1212. The switching TFT 1211 and the driving TFT 1212 are formed so as to have a high-quality crystalline semiconductor film by synthesizing laser light having a fundamental wave and laser light having a wavelength less than or equal to visible light and laser annealing. Is done. Note that the TFT of the pixel portion 1202 does not need to have high crystallinity as compared with the signal line driver circuit 1200 and the scan line driver circuit 1201. The pixel portion 1202 covers the first electrode 1213 of the light emitting element connected to one electrode of the driving TFT 1212, the switching TFT 1211, and the driving TFT 1212, and is in a position corresponding to the first electrode 1213 of the light emitting element. An insulator 1214 having an opening, an electroluminescent layer 1215 provided over the first electrode 1213, and a light-emitting element 1218 including a second electrode 1216 of the light-emitting element provided to face each other. Note that the electroluminescent layer includes an organic material or an inorganic material, and includes an electron injection layer, an electron transport layer, a light emitting layer, a hole transport layer, a hole injection layer, and the like as appropriate.

The insulator 1214 may be formed of an organic resin film such as a resist, polyimide, or acrylic, or an inorganic insulating film containing silicon such as silicon nitride or silicon oxide. Here, the insulator 1214 is formed using a positive photosensitive acrylic resin film. Note that in the case of using an organic resin film or the like, an insulating film containing silicon nitride or silicon nitride oxide as a main component or a DLC film containing hydrogen (Diamond Like Carbon) may be formed in order to prevent intrusion of moisture or oxygen.

Note that a curved surface having a curvature is preferably formed on the upper end portion or the lower end portion of the insulator 1214 in order to improve the step coverage of an electrode or an electroluminescent layer to be formed later. For example, in the case where positive photosensitive acrylic is used as a material for the insulator 1214, only the upper end portion of the insulator 1214 may have a curved surface having a curvature radius (0.2 μm to 3 μm). As the insulator 1214, either a negative type that becomes insoluble in an etchant by photosensitive light or a positive type that becomes soluble in an etchant by light can be used.

Since the first electrode 1213 of the light emitting element is in contact with the first electrode of the driving TFT 1212, at least the lower surface of the first electrode 1213 of the light emitting element is connected to the first electrode region of the semiconductor film. It is desirable to use a material having a high work function on the surface in contact with the electroluminescent layer as a material capable of forming an ohmic contact. For example, the first electrode 1213 of the light-emitting element may be a single layer of a titanium nitride film or a stack of three or more layers. Further, when a light-transmitting conductive film is used for the first electrode 1213 and the second electrode 1216 of the light-emitting element, a display device including a dual-light-emitting light-emitting element can be manufactured.

Depending on the pixel configuration, either the first electrode or the second electrode can be an anode or a cathode. For example, specific electrode materials will be described in the case where the first electrode is an anode and the second electrode is a cathode.

As the anode material, it is preferable to use a metal, an alloy, an electrically conductive compound, a mixture thereof, or the like having a high work function (work function of 4.0 eV or more). Specific examples of the anode material include ITO (indium tin oxide), IZO (indium zinc oxide) in which 2 to 20% zinc oxide (ZnO) is mixed with indium oxide, gold (Au), platinum (Pt), Nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), or metal nitride (TiN), etc. Can be used.

On the other hand, it is preferable to use a metal, an alloy, an electrically conductive compound, a mixture thereof, or the like having a small work function (work function of 3.8 eV or less) as the cathode material. Specific examples of the cathode material include elements belonging to Group 1 or Group 2 of the element periodic rule, that is, alkali metals such as Li and Cs, alkaline earth metals such as Ca and Sr, Mg, and alloys containing these (Mg : Ag, Al: Li) and compounds (LiF, CsF, CaF ₂ ), as well as transition metals including rare earth metals. However, since the cathode needs to have translucency, these metals or an alloy containing these metals are formed very thinly, and are formed by lamination with a metal (including an alloy) such as ITO. These anode and cathode can be formed by vapor deposition, sputtering, or the like.

Further, in the case of full-color display as the electroluminescent layer 1215, materials that emit red (R), green (G), and blue (B) light are selected by an evaporation method using an evaporation mask or an inkjet method, respectively. It may be formed automatically. Specifically, CuPc or PEDOT is used as HIL, α-NPD is used as HTL, BCP or Alq _{3 is used} as ETL, and BCP: Li or CaF ₂ is used as EIL. Further, for example, EML may be Alq ₃ doped with a dopant corresponding to each emission color of R, G, and B (DCM in the case of R, DMQD in the case of G). In addition, it is not limited to the laminated structure of the said organic compound layer.

More specifically, in the case of forming an organic compound layer that emits red light, for example, CuPc is formed to 30 nm, α-NPD is formed to 60 nm, and then the same mask is used to form red. 40 nm of Alq ₃ to which DCM ₂ and rubrene are added is formed as the light emitting layer, 40 nm of BCP is formed as the electron transport layer, and 1 nm of BCP to which Li is added is formed as the electron injection layer. In the case of forming an organic compound layer that emits green light, for example, CuPc is formed to 30 nm and α-NPD is formed to 60 nm, and then coumarin 545T is added as a green light emitting layer using the same vapor deposition mask. Alq ₃ is formed to 40 nm, BCP is formed to 40 nm as an electron transport layer, and BCP doped with Li is formed to 1 nm as an electron injection layer. In the case of forming an organic compound layer that emits blue light, for example, CuPc is formed to 30 nm, α-NPD is formed to 60 nm, and bis [2- (2-hydroxyphenyl) is formed as the light emitting layer using the same mask. ) Benzoxazolate] Zinc: Zn (PBO) ₂ is formed to 10 nm, BCP is formed to 40 nm as the electron transport layer, and BCP doped with Li is formed to 1 nm as the electron injection layer.

As described above, among the organic compound layers of the respective colors, common CuPc and α-NPD can be formed on the entire surface of the pixel portion. The mask can also be shared by each color. For example, after forming the red organic compound layer, the mask can be shifted to form the green organic compound layer, and the mask can be shifted again to form the blue organic compound layer. . What is necessary is just to set the order of the organic compound layer of each color to form suitably.

In the case of white light emission, full color display may be performed by separately providing a color filter or a color filter and a color conversion layer. The color filter and the color conversion layer are provided on the second substrate. After that, the first substrate and the second substrate may be attached to each other.

Further, in order to prevent deterioration of the light-emitting element due to moisture, oxygen, or the like, a protective film 1217 is provided to cover the second electrode of the light-emitting element. In this embodiment, an insulating film mainly containing silicon nitride or silicon nitride oxide obtained by a sputtering method (DC method or RF method) or a DLC film containing hydrogen (Diamond Like Carbon) is used for the protective film 1217.

Then, the second electrode 1216 of the light-emitting element is connected to the connection wiring 1208 through a lead-out wiring from an opening (contact) provided in the insulator 1214 in the connection region. The connection wiring 1208 is connected to a flexible printed circuit board (FPC) 1209 by an anisotropic conductive resin (ACF). Then, a video signal and a clock signal which are external input signals are received via the FPC 1209. Although only the FPC is shown here, a printed wiring board (PWB) may be attached to the FPC.

In this embodiment mode, a driver-integrated light emitting device in which the signal line driver circuit 1200 and the scan line driver circuit 1201 are formed over the first substrate 1210 is shown; however, the signal line driver circuit and the scan line driver circuit are formed using an IC. Then, it may be connected to a signal line, a scanning line, or the like by an SOG method or a TAB method.

Also, when the ACF is bonded by pressurization or heating, care should be taken not to cause cracks due to the flexibility of the substrate and softening due to heating. For example, a highly rigid substrate may be disposed as an auxiliary in the adhesion region.

In addition, a sealant 1205 is provided on a peripheral portion of the first substrate, and is bonded to the second substrate 1204 and sealed. The sealing material 1205 is preferably an epoxy resin.

When sealed with the second substrate 1204, a space is formed between the protective film 1217 and the second substrate 1204. The space is filled with an inert gas, for example, nitrogen gas, or a material with high water absorption is formed to prevent moisture and oxygen from entering. In this embodiment, a resin 1230 having a light-transmitting property and high water absorption is formed. Since the resin 1230 has a light-transmitting property, the resin 1230 can be formed without reducing transmittance even when light from the light-emitting element is emitted (emitted) to the second substrate side.

As described above, a high-performance thin film transistor and a light-emitting device including the thin film transistor can be manufactured with high throughput and low cost.

(Embodiment 6)
In this embodiment, a liquid crystal display device manufactured using a laser irradiation method will be described.

FIG. 6A illustrates a liquid crystal display device in which a signal line driver circuit 1200, a scan line driver circuit 1201, and a pixel portion 1202 are formed over a first substrate 1210.

6B is a cross-sectional view taken along the line AA ′ of the display device. A signal line driver circuit 1200 including a CMOS circuit having an n-channel TFT 1223 and a p-channel TFT 1224 over a first substrate 1210 is shown. Show. The n-channel TFT 1223 and the p-channel TFT 1224 have a high-quality crystalline semiconductor film by synthesizing a laser beam having a fundamental wave and a laser beam having a wavelength less than or equal to visible light, and performing laser annealing. Formed. The TFTs forming the signal line driver circuit 1200 and the scanning line driver circuit 1201 may be formed of a CMOS circuit, a PMOS circuit, or an NMOS circuit.

The pixel portion 1202 includes a switching TFT 1211 and a capacitor element 1245. The switching TFT 1211 is formed to have a high-quality crystalline semiconductor film by synthesizing laser light having a fundamental wave and laser light having a wavelength shorter than or equal to visible light and laser annealing. The capacitor 1245 includes a gate insulating film sandwiched between a semiconductor film to which an impurity is added and a gate electrode. Note that the TFT of the pixel portion 1202 does not need to have high crystallinity as compared with the signal line driver circuit 1200 and the scan line driver circuit 1201. The pixel electrode 1250 connected to one electrode of the switching TFT 1211 is provided, and an insulator 1214 is provided so as to cover the n-channel TFT 1223, the p-channel TFT 1224, the pixel electrode 1250, and the switching TFT 1211.

A second substrate 1204 which is a counter substrate is provided with a black matrix 1253 at a position corresponding to the signal line driver circuit 1200 and a color filter 1252 at least at a position corresponding to a pixel portion. Then, the second substrate 1204 over which the counter electrode 1251 is formed is subjected to rubbing treatment, and is bonded to the first substrate 1210 with a spacer 1255 interposed therebetween.

A liquid crystal layer is injected between the first substrate 1210 and the second substrate 1204. In the case of injecting the liquid crystal layer, it may be performed in a vacuum. Alternatively, a liquid crystal layer may be dropped on the first substrate 1210 and attached to the second substrate 1204. In particular, for a large substrate, it is preferable to drop the liquid crystal layer rather than injecting it.

The first substrate 1210 and the second substrate 1204 are bonded using a sealant 1205. The first substrate 1210 and the second substrate 1204 may be provided with polarizing plates as appropriate to increase contrast.

As described above, a high-performance thin film transistor and a liquid crystal display device including the thin film transistor can be manufactured with high throughput and low cost.

(Embodiment 7)
As an example of an electronic device manufactured by applying the present invention, a digital camera, a sound reproduction device such as a car audio, a notebook personal computer, a game device, a portable information terminal (a mobile phone, a portable game machine, etc.), a home use An image reproducing device including a recording medium such as a game machine may be used. Specific examples of these electronic devices are shown in FIGS.

FIG. 7A illustrates a display device, which includes a housing 2001, a support base 2002, a display portion 2003, a speaker portion 2004, a video input terminal 2005, and the like. The display portion 2003 includes a light-emitting element or a liquid crystal element. The thin film transistor formed by laser irradiation of the present invention can be used for the display portion 2003. Further, since the display device can be manufactured with high throughput and low cost, the cost of the display device can be reduced.

FIG. 7B shows a digital still camera, which includes a main body 2101, a display portion 2102, an image receiving portion 2103, operation keys 2104, an external connection port 2105, a shutter 2106, and the like. The display portion 2102 includes a light-emitting element or a liquid crystal element. The thin film transistor formed by laser irradiation of the present invention can be used for the display portion 2102. Further, since it can be manufactured with high throughput and low cost, the cost of the digital still camera can be reduced.

FIG. 7C illustrates a laptop personal computer, which includes a main body 2201, a housing 2202, a display portion 2203, a keyboard 2204, an external connection port 2205, a pointing mouse 2206, and the like. The display portion 2203 includes a light-emitting element or a liquid crystal element. The thin film transistor formed by laser irradiation of the present invention can be used for the display portion 2203. Further, since it can be manufactured with high throughput and low cost, the cost of a notebook personal computer can be reduced.

FIG. 7D illustrates a mobile computer, which includes a main body 2301, a display portion 2302, a switch 2303, operation keys 2304, an infrared port 2305, and the like. The display portion 2302 includes a light-emitting element or a liquid crystal element. The thin film transistor formed by laser irradiation of the present invention can be used for the display portion 2302. Further, since it can be manufactured with high throughput and low cost, the cost of the mobile computer can be reduced.

FIG. 7E illustrates a portable image reproducing device provided with a recording medium, which includes a main body 2401, a housing 2402, a display portion A2403, a display portion B2404, a recording medium reading portion 2405, operation keys 2406, a speaker portion 2407, and the like. Including. A display portion A2403 mainly displays image information, and a display portion B2404 mainly displays character information. The display portion A 2403 and the display portion B 2404 each include a light-emitting element or a liquid crystal element. The thin film transistor formed by laser irradiation of the present invention can be used for the display portion A 2403 and the display portion B 2404. Further, since the image can be manufactured with high throughput and low cost, the cost of the image reproducing device can be reduced.

FIG. 7F shows a goggle type display which includes a main body 2501, a display portion 2502, and an arm portion 2503. The display portion 2502 includes a light-emitting element or a liquid crystal element. The thin film transistor formed by laser irradiation of the present invention can be used for the display portion 2502. Furthermore, since it can be manufactured with high throughput and low cost, the cost of the goggle type display can be reduced.

FIG. 7G illustrates a video camera, which includes a main body 2601, a display portion 2602, a housing 2603, an external connection port 2604, a remote control receiving portion 2605, an image receiving portion 2606, a battery 2607, an audio input portion 2608, operation keys 2609, and the like. . The display portion 2602 includes a light-emitting element or a liquid crystal element. The thin film transistor formed by laser irradiation of the present invention can be used for the display portion 2602. In addition, since the video camera can be manufactured with high throughput and low cost, the cost of the video camera can be reduced.

FIG. 7H illustrates a mobile phone among mobile terminals, which includes a main body 2701, a housing 2702, a display portion 2703, an audio input portion 2704, an audio output portion 2705, operation keys 2706, an external connection port 2707, an antenna 2708, and the like. Including. The display portion 2703 includes a light-emitting element or a liquid crystal element. The thin film transistor formed by laser irradiation of the present invention can be used for the display portion 2703. Further, since it can be manufactured with high throughput and low cost, the cost of the mobile phone can be reduced.

In the above electronic device, by performing laser irradiation of the present invention, a highly functional thin film transistor and an electronic device having the thin film transistor can be provided, and the electronic device can be manufactured with high throughput and low cost.

This embodiment mode can be freely combined with the above embodiment modes.

The figure which shows the laser irradiation apparatus of this invention. The figure which shows the laser irradiation apparatus of this invention. The figure which shows the laser irradiation apparatus of this invention. 4A and 4B illustrate a method for manufacturing a TFT using laser irradiation according to the present invention. FIG. 6 shows a light-emitting device manufactured using laser irradiation according to the present invention. 4A and 4B illustrate a liquid crystal display device manufactured using laser irradiation according to the present invention. FIG. 14 illustrates an electronic device manufactured using laser irradiation according to the present invention.

Claims (20)

A laser resonator that outputs a fundamental wave and a wavelength equal to or less than the fundamental wave; and
Means for relatively moving the object to be irradiated and the laser beam from the laser resonator;
Means for processing the laser beam into a linear laser;
A laser irradiation apparatus comprising:
The laser irradiation apparatus characterized in that the means for processing the linear laser has means for condensing laser light having the fundamental wave and a wavelength shorter than the fundamental wave. A laser resonator that outputs a fundamental wave and a wavelength equal to or less than the fundamental wave; and
Means for relatively moving the object to be irradiated and the laser beam from the laser resonator;
Means for processing the laser beam into a linear laser;
A laser irradiation apparatus comprising:
The laser resonator includes an excitation source, a laser medium, and a nonlinear optical element, and the means for processing the linear laser includes means for condensing the fundamental wave and laser light having a wavelength equal to or less than the fundamental wave. A laser irradiation apparatus comprising: 3. The laser irradiation apparatus according to claim 1, wherein the laser resonator is a pulse oscillation type or a continuous oscillation type laser resonator. 4. The laser irradiation apparatus according to claim 1, wherein the means for condensing the fundamental wave and the wavelength below the fundamental wave is a concave mirror or an achromatic lens. 5. The laser irradiation apparatus according to claim 1, wherein the wavelength equal to or shorter than the fundamental wave is a harmonic wave obtained by converting the fundamental wave by the nonlinear optical element. 6. The laser irradiation apparatus according to claim 1, wherein the wavelength equal to or shorter than the fundamental wave is a second harmonic wave obtained by converting the fundamental wave by the nonlinear optical element. 7. The laser resonator according to claim 1, wherein the laser resonator includes YAG, YLF, YVO ₄ , Y ₂ O ₃ , glass, sapphire, forsterite doped with Nd, Yb, Ti, Cr, Ho, and Er ions. , LuAg, and LuLiF ₄ as a laser medium. A method of irradiating a laser beam having a fundamental wave emitted from one laser resonator and a wavelength equal to or less than the fundamental wave in which the fundamental wave is deformed by a nonlinear optical element,
Irradiating the same irradiation surface at the same time without separating the fundamental wave and the wavelength below the fundamental wave. A method of irradiating a fundamental wave emitted from one laser resonator having a nonlinear optical element, and a laser beam having a wavelength equal to or less than the fundamental wave,
Irradiating the same irradiation surface at the same time without separating the fundamental wave and the wavelength below the fundamental wave. 10. The laser irradiation method according to claim 8, wherein the wavelength equal to or shorter than the fundamental wave is a harmonic obtained by converting the fundamental wave by the nonlinear optical element. 11. The laser irradiation method according to claim 8, wherein the wavelength equal to or shorter than the fundamental wave is a second harmonic wave obtained by converting the fundamental wave by the nonlinear optical element. In any one of Claims 8 thru | or 11,
The laser beam is processed into a linear laser, the length of the major axis or minor axis on the surface of the irradiated object is W, the substrate has translucency with respect to the linear laser beam, and the irradiated object is placed on the substrate Where d is the thickness of
The incident angle φ of the linear laser beam is
φ ≧ arctan (W / 2d)
Irradiation is performed so as to satisfy the above conditions. In any one of claims 8 to 12, wherein the laser beam is, Nd, Yb, Ti, Cr , Ho, YAG doped with Er _{ions, YLF, YVO 4, Y 2} O 3, glass, sapphire, forsterite, A laser irradiation method characterized by oscillating a solid of any one of LuAg and LuLiF ₄ as a laser medium. 14. The laser irradiation method according to claim 8, wherein the laser beam emitted from the laser resonator is a pulsed or continuous wave laser beam. Irradiating an amorphous semiconductor film formed on an insulating surface with a laser beam having a fundamental wave emitted from one laser resonator and a wavelength equal to or less than the fundamental wave obtained by deforming the fundamental wave by a nonlinear optical element A method of manufacturing a semiconductor device for crystallizing the amorphous semiconductor film,
A method for manufacturing a semiconductor device, wherein the fundamental wave and a wavelength equal to or less than the fundamental wave are irradiated simultaneously and on the same irradiation surface without being separated. By irradiating an amorphous semiconductor film formed on an insulating surface with a fundamental wave emitted from one resonator having a nonlinear optical element and a laser beam having a wavelength equal to or less than the fundamental wave, the amorphous semiconductor film is formed. A method for manufacturing a semiconductor device for crystallizing a semiconductor film,
A method for manufacturing a semiconductor device, wherein the fundamental wave and a wavelength equal to or less than the fundamental wave are irradiated simultaneously and on the same irradiation surface without being separated. 17. The method for manufacturing a semiconductor device according to claim 15, wherein the wavelength equal to or shorter than the fundamental wave is a harmonic wave obtained by converting the fundamental wave by the nonlinear optical element. 18. The method for manufacturing a semiconductor device according to claim 15, wherein the wavelength equal to or shorter than the fundamental wave is a second harmonic wave obtained by converting the fundamental wave by the nonlinear optical element. In any one of claims 15 to 18, wherein the laser beam is, Nd, Yb, Ti, Cr , Ho, YAG doped with Er _{ions, YLF, YVO 4, Y 2} O 3, glass, sapphire, forsterite, A method for manufacturing a semiconductor device, characterized by oscillating a solid of any one of LuAg and LuLiF ₄ as a laser medium. 20. The method for manufacturing a semiconductor device according to claim 15, wherein the laser light emitted from the laser resonator is a pulsed or continuous wave laser beam.

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