JP2004039890A - Laser irradiating apparatus and semiconductor film crystallizing method using the same and semiconductor device manufacturing process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser irradiating apparatus for providing a crystalline semiconductor film in which, by controlling a Marangoni convection occurring on the surface of a liquid solution in laser annealing, crystallinity is excellent and besides there is less variation in quality, then to provide a semiconductor film crystallizing method using the same, and further to provide a semiconductor device using an FET for attaining high electric field effect mobility by the crystalline semiconductor film made by the crystallizing method. <P>SOLUTION: An amorphous semiconductor film is once molten and when performing crystallization in a subsequent process, a magnetic field is applied to the surface or zone of the molten film with the principal aim of controlling the Marangoni convection in a surface of the molten film. The Maragoni convection is controlled by applying the magnetic field to prevent oxygen that has been taken in the semiconductor from segregating locally even if the molten zone is formed in an atmosphere containing oxygen, enabling the oxygen to be dispersed homogeneously in the formed crystalline semiconductor film. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a laser irradiation apparatus used for crystallization of a semiconductor film, a semiconductor film crystallization method using the same, and a method for manufacturing a semiconductor device using the same.
[0002]
[Prior art]
There is known a crystallization technique in which an amorphous silicon film deposited on a glass substrate is irradiated with laser light to form a polycrystalline silicon film. An excimer laser oscillator that performs pulse oscillation is a light source typically used in this crystallization technique. The irradiation of the pulsed laser light instantaneously heats the silicon, temporarily melts it, and crystallizes during the cooling process, and usually forms a polycrystal in which a plurality of crystal grains having different plane orientations are aggregated. Irradiation with pulsed laser light having a pulse width of several tens to several hundreds of nanoseconds can selectively heat silicon, and can perform crystallization without increasing the temperature of the substrate. Therefore, the advantage that an inexpensive substrate such as borosilicate glass having a low heat resistance temperature can be applied is recognized.
[0003]
Needless to say, the crystallization of the semiconductor film on the glass substrate at low temperature is not limited to irradiation with pulsed laser light, but can also be performed by irradiation with continuous oscillation laser light. For example, in "N. Sasaki et al, 2002 SID International Symposium Digest of Technical Papers, pp. 154-157", a lateral crystal growth technique by irradiation of continuous wave laser light is reported, and the technique is manufactured using the technique. An operating frequency of 270 MHz has been reported for shift register circuits.
[0004]
Laser annealing using a continuous wave laser oscillator disclosed in the above document is characterized in that a semiconductor film is heated for a longer time by a laser beam as compared with a case where a pulse laser oscillator represented by an excimer laser is used as a light source. There is. Another feature is that the interface (solid-liquid interface) between the melting region and the solid phase region proceeds in a direction substantially parallel to the substrate surface, and the crystal extends in that direction.
[0005]
[Problems to be solved by the invention]
It has been known from past empirical knowledge that when crystallization of an amorphous silicon film by laser annealing is performed in an atmosphere containing oxygen, a large grain size can be achieved (for example, And JP-A-2001-15435). Therefore, in many cases, laser annealing was performed in the air.
[0006]
The demand for a larger crystal grain is to improve the field-effect mobility of a TFT manufactured using the crystal, and an ideal one is to make it equivalent to a MOS transistor formed on a single crystal silicon substrate. It is perceived as a form. The method of crystallization while continuously moving the solid-liquid interface by scanning with a continuous wave laser beam is considered to be a method similar to the zone melting method, and it is possible to increase the particle size by continuous crystal growth. . However, even if the crystal has a large grain size, the problem that the characteristics vary among a plurality of TFTs formed on the same substrate has often become apparent.
[0007]
Regarding this problem, the present inventor has found a new factor that has not been recognized so far in the laser annealing method. In other words, the crystallization of a continuous wave laser beam that has a melting state longer than the pulse laser beam increases the rate at which impurities are taken into the crystal from the outside, and this is caused by surface tension convection (Marangoni convection) on the melt surface. It did not disperse uniformly but segregated locally, which eventually resulted in a change in crystal quality, which could be considered to be a cause of TFT characteristic variations.
[0008]
The present invention has been made in view of such a problem. The present invention controls surface tension convection (Marangoni convection) on the surface of a melt in a laser annealing method, and has excellent crystallinity and a variation in quality. A laser irradiation apparatus for providing a small number of crystalline semiconductor films, a method for crystallizing a semiconductor film using the same, and a semiconductor using a field-effect transistor for realizing high field-effect mobility in a crystalline semiconductor film produced by the laser irradiation apparatus It is intended to provide a device.
[0009]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention mainly controls the surface tension convection (Marangoni convection) of the molten surface when the amorphous semiconductor film is once melted and crystallized in a subsequent cooling process. For the purpose, a magnetic field is applied to a molten surface or a molten zone. By applying a magnetic field, surface tension convection (Marangoni convection) is suppressed, and even if a molten zone is formed in an atmosphere containing oxygen, oxygen sequestered in the semiconductor is prevented from locally segregating, and the crystallinity formed is reduced. It is possible to uniformly disperse in a semiconductor film.
[0010]
A laser irradiation apparatus according to the present invention that achieves the above object includes a continuous wave laser oscillator, an optical system that linearly condenses laser light using the same as a light source on an irradiation surface, and an irradiation surface for an object to be irradiated. The apparatus includes scanning means for moving, and magnetic field applying means for forming a magnetic field in an irradiation surface or a space including the irradiation surface. As the magnetic field applying means, a normal conducting coil, a superconducting coil, a permanent magnet and the like can be applied.
[0011]
The method for crystallizing a semiconductor film according to the present invention is characterized in that the semiconductor film is partially heated to form a molten zone, and the solid-liquid interface is continuously moved to be crystallized. And crystallization of the semiconductor film while suppressing a surface tension convection (Marangoni convection) on the surface of the molten zone by applying a magnetic field to the semiconductor layer. The molten zone is formed by irradiating a semiconductor film with continuous wave laser light, and the molten zone is preferably formed in an atmosphere containing oxygen. It is preferable that the melting zone or the solid-liquid interface is moved so that the melting time of the semiconductor film is 10 μsec to 500 μsec.
[0012]
The method for crystallizing a semiconductor film according to the present invention is characterized in that a semiconductor layer formed on an insulating surface is partially heated to form a molten zone, and the solid-liquid interface is continuously moved for crystallization. A magnetic field is applied to the melt zone or the solid-liquid interface to crystallize the semiconductor film while suppressing surface tension convection on the melt zone surface, and the channel portion of the insulated gate field effect transistor is formed on the formed crystalline semiconductor film. Is formed. The molten zone is formed by irradiating a semiconductor film with continuous wave laser light, and the molten zone is preferably formed in an atmosphere containing oxygen. It is preferable that the melting zone or the solid-liquid interface is moved so that the melting time of the semiconductor film is 10 μsec to 500 μsec.
[0013]
In the above structure of the present invention, the magnetic field controls the concentration and distribution of oxygen taken into the semiconductor film by the horizontal magnetic field, the vertical magnetic field, and the caps magnetic field with respect to the irradiation surface or the melting zone. Alternatively, the concentration and distribution of oxygen taken into the semiconductor film by a horizontal magnetic field, a vertical magnetic field, and a caps magnetic field in the moving direction of the melting zone are controlled.
[0014]
Since oxygen has two coordinates, it is incorporated into a four-coordinate silicon network to increase structural flexibility and to reduce dangling bonds caused by dislocation and the like. Oxygen supplied to the crystal grain boundaries reacts with dangling bonds existing there to form bonds. Since the degree of freedom in coupling is increased, defects caused by lattice distortion can be compensated.
[0015]
However, the supply of a large amount of oxygen causes the crystal structure of silicon to collapse, and on the contrary, increases defects. According to an average concentration evaluation method measured by secondary ion mass spectrometry (SIMS), the oxygen concentration applied in the present invention is desirably 5 × 10 ¹⁷ to 2 × 10 ¹⁹ / cm ^3. . However, in addition to oxygen taken in from the atmosphere (in the gas phase) at the time of laser annealing, oxygen included in the semiconductor film from the beginning, and natural oxidation formed on the surface of the semiconductor film are used in the present invention. It also includes oxygen in the film, oxygen supplied from a base in contact with the semiconductor film, and the like.
[0016]
Note that the term “amorphous semiconductor film” in the present invention means not only a film having a completely amorphous structure in a narrow sense, but also a state in which fine crystal grains are contained, or a so-called microcrystalline semiconductor film, Includes a semiconductor film having a crystal structure. Typically, an amorphous silicon film is applied. In addition, an amorphous silicon germanium film, an amorphous silicon carbide film, or the like can be used.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, it is easily understood by those skilled in the art that the present invention can be implemented in many different modes, and that the form and details can be variously changed without departing from the spirit and scope of the present invention. Is done. Therefore, the present invention is not construed as being limited to the description of the embodiments. The same elements are denoted by the same reference numerals throughout the embodiments described below.
[0018]
FIG. 6 is a diagram showing main components of the laser irradiation apparatus according to the present invention and their relationships. The laser irradiation apparatus includes an optical system 100 including a laser oscillator 101, a wavelength conversion element 102, a high conversion mirror 103, cylindrical lenses 104 and 105, a slit 106, and the like, for condensing laser light linearly on an irradiation surface, a mounting table 109. The main component is the magnetic field applying means 107 placed on the periphery of the mounting table. In addition, a gas supply unit 108 for controlling an atmosphere to which the object 110 is exposed may be provided as an additional component. Atmosphere control is used particularly when oxygen is positively contained or not.
[0019]
As the laser oscillator 101, a rectangular beam solid laser oscillator is applied, and particularly preferably, a slab laser oscillator is applied. Alternatively, a solid-state laser oscillator using a crystal in which Nd, Tm, or Ho is doped with a crystal such as YAG, YVO ₄ , YLF, or YAlO ₃ may be combined with a slab structure amplifier. As the slab material, a crystal such as Nd: YAG, Nd: GGG (gadolinium gallium garnet), or Nd: GsGG (gadolinium scandium gallium garnet) is used. In addition, a gas laser oscillator or a solid laser oscillator capable of continuous oscillation can be used. As a continuous wave solid laser oscillator, a laser oscillator using a crystal such as YAG, YVO ₄ , YLF, or YAlO ₃ doped with Cr, Nd, Er, Ho, Ce, Co, Ti, or Tm is used. The fundamental wave of the oscillation wavelength varies depending on the material to be doped, but oscillates at a wavelength of 1 μm to 2 μm. In order to obtain a higher output of 5 W or more, a diode-pumped solid-state laser oscillator may be cascaded.
[0020]
The circular or rectangular laser light output from such a laser oscillator is condensed linearly by the cylindrical lenses 104 and 105 in the cross-sectional shape of the irradiation surface. Further, in order to prevent interference on the irradiation surface, the high-conversion mirror 103 may be appropriately adjusted so that the light enters from an oblique direction at an angle of 10 to 80 degrees. If the cylindrical lenses 104 and 105 are made of synthetic quartz, a high transmittance can be obtained, and a coating applied to the lens surface is applied to achieve a transmittance of 99% or more with respect to the wavelength of laser light. Of course, the cross-sectional shape of the irradiation surface is not limited to a linear shape, and may be an arbitrary shape such as a rectangular shape, an elliptical shape, or an oval shape. In any case, the ratio of the short axis to the long axis is in the range of 1:10 to 1: 1100. Further, the wavelength conversion element 102 is provided for obtaining a harmonic with respect to the fundamental wave.
[0021]
Further, the mounting table 109 can be subjected to laser processing on the entire surface of the processing object 110 by moving the mounting table 109 in two axial directions by a driving unit. The movement in one direction can be continuously performed at a constant speed of 1 to 200 cm / sec, preferably 5 to 50 cm / sec over a distance longer than the length of one side of the substrate 420, and linear in the other direction. It is possible to step-discontinuously move the same distance as the longitudinal direction of the beam. The focusing width of the laser light is approximately 5 to 50 μm, and by applying the above scanning speed,
A melting time of 10 μsec to 50 μsec is achieved.
[0022]
As the magnetic field applying means, an electromagnet such as a superconducting coil or a normal conducting coil or a permanent magnet is applied, and the magnetic field applying means is arranged around the object 110 to form a magnetic field of about 500 to 10,000 gauss. The magnetic field is selected from an arrangement that enables formation of a horizontal magnetic field, a vertical magnetic field, and a cusp magnetic field, depending on the relative positional relationship with the molten zone formed on the workpiece by laser light irradiation.
[0023]
When the amorphous semiconductor film is irradiated with laser light in the air to form a molten zone, oxygen reacts with the air to be dissolved therein. As another oxygen inflow route, there is oxygen in a glass substrate underlying the amorphous semiconductor film or a silicon oxide film formed on the surface thereof. The application of the magnetic field suppresses the surface tension convection (Marangoni convection), prevents the molten zone from solidifying and locally segregates oxygen, and has the effect of uniformly dispersing oxygen. In addition, it becomes possible to control the oxygen concentration in the crystallization region by the method of applying a magnetic field. That is, oxygen can be intentionally included. In any case, it is important to properly use the method of applying a magnetic field according to the purpose depending on the form of crystallization.
[0024]
The form of applying a magnetic field shown in FIG. 2 is an example in which a magnetic field is applied in a direction perpendicular to a molten zone 112 formed in a semiconductor film 111 on a substrate 110. In this case, it is assumed that the molten zone 112 moves in a direction perpendicular to the plane of the drawing. As the magnetic field applying means 107, a toroidal coil may be applied.
[0025]
The form of applying a magnetic field shown in FIG. 3 is an example in which a magnetic field is applied in a horizontal direction to a molten zone 112 formed in a semiconductor film 111 on a substrate 110. In this case, it is assumed that the molten zone 112 moves in a direction perpendicular to the plane of the drawing. FIG. 6 shows this state as viewed from above. As the magnetic field applying means 107, a toroidal coil may be applied. On the other hand, by changing the arrangement of the magnetic field applying means, as another mode of applying a magnetic field in the horizontal direction, a magnetic field can be applied in a direction parallel to the moving direction of the molten zone 112.
[0026]
The form of applying a magnetic field shown in FIG. 4 is an example in which a cusp magnetic field is applied to a molten zone 112 formed in a semiconductor film 111 on a substrate 110. In this case, it is assumed that the molten zone 112 moves in a direction perpendicular to the plane of the drawing. As the magnetic field applying means 107, a toroidal coil may be applied. The position of the cusp magnetic field center can take three types: above the melting zone 112, at the center of the melting zone 112, and below the melting zone 112. When the center of the cusp magnetic field is the center of the melting zone 112, a magnetic force acts outward from the center of the melting zone 112. On the other hand, as shown in FIG. 5, a cusp magnetic field can be applied in a direction perpendicular to the melting zone 112.
[0027]
FIGS. 8 and 9 show the relative positional relationship between the moving direction of the melting zone 112 and the cusp magnetic field. This shows a mode in which the direction of the magnetic field component Hp acting in a direction parallel to the moving direction of the melting zone 112 and the direction of the magnetic field component Hc acting in the direction intersecting are made different.
[0028]
As a most preferred example of a method for manufacturing a semiconductor device of the present invention, in a mode in which a magnetic field is applied to form a molten zone in an amorphous semiconductor film and a solid-liquid interface is continuously moved to grow a crystal, It is desirable to irradiate continuous wave laser light selected from a wavelength band having a coefficient of 5 × 10 ^{4 to} 2 × 10 ⁵ / cm. This aims at completely melting the amorphous semiconductor film by absorbing the laser light inside the amorphous semiconductor film and heating it from the inside. For example, the second harmonic (532 nm) of a Nd: YVO ₄ laser oscillator is applied to an amorphous silicon film.
[0029]
FIG. 10 illustrates a method for manufacturing a semiconductor device according to the present invention. In FIG. 10A, a base insulating film 202 including a single layer or a stack of a silicon nitride film, a silicon oxide film, and a silicon oxynitride film is formed over a substrate 201. As a member to be the substrate 201, a glass material called a non-alkali glass, which is a commercially available product such as aluminosilicate glass, can be applied. Alternatively, a semiconductor substrate such as single crystal silicon can be used.
[0030]
The crystalline semiconductor film 203 is crystallized by applying a magnetic field to the amorphous semiconductor film and irradiating the amorphous semiconductor film with laser light. As the amorphous semiconductor film, silicon or an amorphous material in which germanium is added to silicon is used. The thickness of the crystalline semiconductor film is 30 to 200 nm, typically 150 nm.
For crystallization, continuous wave laser light is irradiated, and the second harmonic (532 nm) is applied using a YVO ₄ laser oscillator as a light source. A beam obtained by condensing a laser beam having an output of 6 W (second harmonic) of a light source at about 500 μm × 20 μm is scanned at a speed of 5 to 100 cm / sec, preferably 25 to 50 cm / sec. A magnetic field of 500 to 5000 Gauss is applied. Further, the crystalline semiconductor film 203 is the same as that obtained by recrystallizing an amorphous semiconductor film by applying a magnetic field and irradiating a laser beam.
[0031]
Next, as shown in FIG. 10B, semiconductor films 201 to 203 which are isolated and isolated in an island shape by etching into a desired shape are formed from the crystalline semiconductor film formed over the base insulating film 102 of the substrate 101. I do. These semiconductor films 201 to 203 form channel forming regions, source and drain regions, low-concentration impurity regions, and the like, and become main components of a TFT. In order to etch the crystalline semiconductor film, a mixed gas of CF ₄ and O ₂ is used as an etching gas by using a dry etching method, and the end portions of the semiconductor films 201 to 203 are formed in order to improve the coverage of the gate insulating film. Is processed so as to have a taper angle of 30 to 60 degrees.
[0032]
Next, semiconductor films 204 to 206 are formed (FIG. 10B), and a silicon oxide film 207 and a silicon nitride film 208 for forming a gate insulating film are formed thereon by a high-frequency magnetron sputtering method to form a gate electrode. Four layers of the first conductive film 209 and the second conductive film 210 are continuously formed under reduced pressure without exposure to the air (FIG. 10C).
[0033]
First, the surfaces of the semiconductor films 204 to 206 are cleaned and smoothed by an oxidation treatment using an aqueous solution containing ozone water and an oxide film removal treatment using an aqueous solution containing hydrofluoric acid, and the surface of the semiconductor film is etched to remove a surface layer portion. I do. By this treatment, the outermost surfaces of the semiconductor films 204 to 206 are etched, so that a clean and inert surface terminated with hydrogen can be formed. In the step of forming the gate insulating film, heat treatment at 100 to 200 ° C. is performed under reduced pressure in order to remove moisture attached to the substrate and the surface of the substrate and to clean the substrate.
[0034]
The gate insulating film in this embodiment has a two-layer structure of a silicon oxide film 207 formed using silicon as a target by a high-frequency magnetron sputtering method and a silicon nitride film 208. The main film formation conditions of the silicon oxide film, using _{O 2} and Ar as the sputtering gas, is formed to a thickness of 10~60nm as the substrate heating temperature 100 to 200 ° C.. Thereafter, lamp annealing is performed at 600 to 750 ° C. for 30 to 180 seconds. Under these conditions, a dense silicon oxide film 207 having a low interface state density with the semiconductor film can be formed. Silicon nitride film 208, using _{N 2} and Ar as the sputtering gas, likewise heated to 100 to 200 ° C. to a thickness of 10 to 30 nm. Since the relative permittivity of silicon nitride is about 7.5 in comparison to the relative permittivity of silicon oxide of 3.8, by including a silicon nitride film in a gate insulating film formed of a silicon oxide film, It is possible to obtain the same effect as reducing the thickness of the insulating film. With a two-layer structure of a silicon oxide film and a silicon nitride film in the gate insulating film, the gate leakage current is reduced even when the total thickness of the gate insulating film is 30 to 80 nm, and the gate insulating film has a typical thickness of 2.5 to 10 V, typically 2.5 to 10 V. Can drive the TFT at 3.0 to 5.5V.
[0035]
As described above, in this embodiment, a gate insulating film having a two-layer structure is employed. However, a silicon oxide film formed using TEOS by a plasma CVD method or a nitride film formed by reacting SiH ₄ with a nitric oxide gas is used. A silicon oxide film may be used.
[0036]
Further, contaminants at the interface between the gate insulating film and the gate electrode also cause a change in the threshold voltage or the like. Therefore, after forming the gate insulating film, a 10- to 50-nm-thick tantalum nitride (TaN) film is successively formed. One conductive film 209 and a second conductive film 210 made of tungsten (W) with a thickness of 100 to 400 nm are formed by lamination.
[0037]
The gate electrode is formed by processing this laminated film. Other applicable conductive materials are elements selected from Ta, W, Ti, Mo, Al, and Cu, or alloys containing the element as a main component. It is formed of a material or a compound material. Alternatively, a semiconductor film typified by a polycrystalline silicon film doped with an impurity element such as phosphorus may be used. The first conductive film is formed of a tantalum (Ta) film, the second conductive film is formed of a W film, the first conductive film is formed of a tantalum nitride (TaN) film, and the second conductive film is formed of an Al film. Alternatively, the first conductive film may be formed of a tantalum nitride (TaN) film, and the second conductive film may be formed of a Cu film.
[0038]
Next, as shown in FIG. 10D, a resist mask 211 for forming a gate electrode pattern by photolithography is formed. After that, a first etching process is performed by a dry etching method. Although there is no limitation on the etching gas, it is preferable to use CF ₄ , Cl _2, and O ₂ for etching W or TaN. In the first etching process, a predetermined bias voltage is applied to the substrate side so that the side surface of the formed first-shaped gate electrode pattern 212 has a tilt angle of 15 to 50 degrees. Although depending on the etching conditions, the silicon nitride film 208 formed as the gate insulating film by the first etching process remains under the first shape gate electrode pattern 212, and the silicon oxide film 204 is exposed in other regions. .
[0039]
Thereafter, the W film is anisotropically etched by changing to the second etching condition, using SF ₆ , Cl _2, and O _{2 as} the etching gas and setting the bias voltage applied to the substrate side to a predetermined value. Thus, the gate electrode 213 is formed. After that, the resist mask 211 is removed (FIG. 10E).
[0040]
The gate electrode is a laminated structure of the first conductive film 209 and the second conductive film 210, and has a hat-shaped structure in which the first conductive film 209 protrudes like an eave. After that, as shown in FIG. 10F, a doping process is performed to form an impurity region in each semiconductor film. Doping conditions may be set as appropriate. The first n-type impurity region 215 formed in the semiconductor film 204 forms a low concentration drain, and the second n-type impurity region 216 forms a source or drain region. The first p-type impurity region 218 formed in the semiconductor film 205 forms a source or a drain overlapping the gate electrode, and the second p-type impurity region 219 forms a source or a drain region. The channel formation regions 214 and 217 in each semiconductor film are to be formed at positions substantially overlapping the second conductive film of the gate electrode 213. The semiconductor film 206 is used as a member for forming a capacitor portion, and an impurity is added at the same concentration as the second n-type impurity region or the second p-type impurity region.
[0041]
Then, as shown in FIG. 11A, a silicon oxynitride film 220 containing hydrogen is formed with a thickness of 50 nm by a plasma CVD method, and the semiconductor film is hydrogenated by a heat treatment at 350 to 550 ° C.
[0042]
The interlayer insulating film 221 is formed in a predetermined pattern using a photosensitive organic resin material containing acrylic or polyimide as a main component. Then, a contact hole is formed by dry etching (FIG. 11B).
[0043]
Thereafter, as shown in FIG. 11C, wirings 222 to 224 are formed using Al, Ti, Mo, W, or the like. As an example of the wiring structure, a laminated film of a Ti film having a thickness of 50 to 250 nm and an alloy film (an alloy film of Al and Ti) having a thickness of 300 to 500 nm is used.
[0044]
Thus, an n-channel TFT 301, a p-channel TFT 302, and a capacitor 303 can be formed. In each TFT, at least one silicon nitride film is included in the gate insulating film. Further, in the capacitor portion 303, at least one layer of a silicon nitride film is included as a dielectric film.
[0045]
【The invention's effect】
As described above, according to the present invention, in the laser annealing method in which an amorphous semiconductor film is once melted and then crystallized in a cooling process, the surface tension convection ( By controlling Marangoni convection), even if a molten zone is formed in an atmosphere containing oxygen, oxygen sequestered in the semiconductor is prevented from being locally segregated, and homogeneously formed in the formed crystalline semiconductor film. It is possible to disperse.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a laser irradiation apparatus of the present invention.
FIG. 2 is a diagram illustrating a form in which a magnetic field is applied perpendicularly to a melting zone.
FIG. 3 is a diagram showing a mode in which a magnetic field is applied horizontally to a melting zone.
FIG. 4 is a diagram showing a form in which a cusp magnetic field is applied to a melting zone.
FIG. 5 is a diagram showing a form in which a cusp magnetic field is applied to a melting zone.
FIG. 6 is a diagram showing a mode in which a magnetic field is applied horizontally to a melting zone.
FIG. 7 is a diagram showing a form in which a magnetic field is applied in parallel to the moving direction of the melting zone.
FIG. 8 is a diagram showing a form in which a cusp magnetic field is applied to a melting zone.
FIG. 9 is a diagram showing a form in which a cusp magnetic field is applied to a melting zone.
FIG. 10 illustrates a method for manufacturing a semiconductor device of the present invention.
FIG. 11 illustrates a method for manufacturing a semiconductor device of the present invention.
[Explanation of symbols]
107 Magnetic field applying means 110 Substrate 111 Semiconductor film 112 Melt zone

Claims (10)

A continuous wave laser oscillator, an optical system that condenses laser light using the continuous wave laser as a light source on an irradiation surface of an irradiation object, a scanning unit that moves the irradiation surface, and a magnetic field that forms a magnetic field on the irradiation surface A laser irradiation device, comprising: an application unit. A continuous wave laser oscillator, an optical system that linearly condenses laser light using the light source as a light source on an irradiation surface of an irradiation target, scanning means for moving the irradiation surface, and a magnetic field in a space including the irradiation surface. A laser irradiation apparatus, comprising: a magnetic field applying means for forming. A semiconductor layer is partially heated to form a molten zone, and upon crystallization by continuously moving the solid-liquid interface, a magnetic field is applied to the molten zone or the solid-liquid interface to apply a magnetic field to the molten zone surface. Crystallizing the semiconductor film while suppressing surface tension convection of the semiconductor film. When a continuous oscillation laser beam is applied to the semiconductor film to form a molten zone, and the solid-liquid interface is continuously moved to be crystallized, a magnetic field is applied to the irradiated portion of the laser beam or the solid-liquid interface. A method for crystallizing a semiconductor film, comprising crystallizing the semiconductor film while suppressing surface tension convection in the melting zone. 5. The method according to claim 3, wherein the melting zone is formed in an atmosphere containing oxygen. 5. The method according to claim 3, wherein the melting zone or the solid-liquid interface is moved so that the melting time of the semiconductor film is 10 to 500 [mu] sec. A magnetic field is applied to the molten zone or the solid-liquid interface during crystallization by partially heating the semiconductor film formed on the insulating surface to form a molten zone and continuously moving the solid-liquid interface. A crystallization of the semiconductor film while suppressing surface tension convection on the surface of the molten zone, thereby forming a channel portion of an insulated gate field effect transistor in the formed crystalline semiconductor film. Method for manufacturing the device. The semiconductor film formed on the insulating surface is irradiated with a continuous wave laser beam to form a molten zone, and when the solid-liquid interface is continuously moved to be crystallized, the laser beam is irradiated or solidified. Crystallizing the semiconductor film while applying a magnetic field to a liquid interface to suppress surface tension convection in the melting zone, and forming a channel portion of an insulated gate field effect transistor in the formed crystalline semiconductor film. A method for manufacturing a semiconductor device, comprising: 9. The method according to claim 7, wherein the melting zone is formed in an atmosphere containing oxygen. 9. The method for manufacturing a semiconductor device according to claim 7, wherein the melting zone or the solid-liquid interface is moved so that a melting time of the semiconductor film is 10 to 500 μsec.

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